mount.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 <stdio.h>
  24 #include <mntent.h>
  25 #include <sys/epoll.h>
  26 #include <signal.h>
  27
  28 #include "unit.h"
  29 #include "mount.h"
  30 #include "load-fragment.h"
  31 #include "load-dropin.h"
  32 #include "log.h"
  33 #include "strv.h"
  34 #include "mount-setup.h"
  35 #include "unit-name.h"
  36
  37 static const UnitActiveState state_translation_table[_MOUNT_STATE_MAX] = {
  38         [MOUNT_DEAD] = UNIT_INACTIVE,
  39         [MOUNT_MOUNTING] = UNIT_ACTIVATING,
  40         [MOUNT_MOUNTING_DONE] = UNIT_ACTIVE,
  41         [MOUNT_MOUNTED] = UNIT_ACTIVE,
  42         [MOUNT_REMOUNTING] = UNIT_ACTIVE_RELOADING,
  43         [MOUNT_UNMOUNTING] = UNIT_DEACTIVATING,
  44         [MOUNT_MOUNTING_SIGTERM] = UNIT_DEACTIVATING,
  45         [MOUNT_MOUNTING_SIGKILL] = UNIT_DEACTIVATING,
  46         [MOUNT_REMOUNTING_SIGTERM] = UNIT_ACTIVE_RELOADING,
  47         [MOUNT_REMOUNTING_SIGKILL] = UNIT_ACTIVE_RELOADING,
  48         [MOUNT_UNMOUNTING_SIGTERM] = UNIT_DEACTIVATING,
  49         [MOUNT_UNMOUNTING_SIGKILL] = UNIT_DEACTIVATING,
  50         [MOUNT_MAINTAINANCE] = UNIT_INACTIVE,
  51 };
  52
  53 static const char* const state_string_table[_MOUNT_STATE_MAX] = {
  54         [MOUNT_DEAD] = "dead",
  55         [MOUNT_MOUNTING] = "mounting",
  56         [MOUNT_MOUNTING_DONE] = "mounting-done",
  57         [MOUNT_MOUNTED] = "mounted",
  58         [MOUNT_REMOUNTING] = "remounting",
  59         [MOUNT_UNMOUNTING] = "unmounting",
  60         [MOUNT_MOUNTING_SIGTERM] = "mounting-sigterm",
  61         [MOUNT_MOUNTING_SIGKILL] = "mounting-sigkill",
  62         [MOUNT_REMOUNTING_SIGTERM] = "remounting-sigterm",
  63         [MOUNT_REMOUNTING_SIGKILL] = "remounting-sigkill",
  64         [MOUNT_UNMOUNTING_SIGTERM] = "unmounting-sigterm",
  65         [MOUNT_UNMOUNTING_SIGKILL] = "unmounting-sigkill",
  66         [MOUNT_MAINTAINANCE] = "maintainance"
  67 };
  68
  69 static char *mount_name_from_where(const char *where) {
  70         assert(where);
  71
  72         if (streq(where, "/"))
  73                 return strdup("-.mount");
  74
  75         return unit_name_build_escape(where+1, NULL, ".mount");
  76 }
  77
  78 static void service_unwatch_control_pid(Mount *m) {
  79         assert(m);
  80
  81         if (m->control_pid <= 0)
  82                 return;
  83
  84         unit_unwatch_pid(UNIT(m), m->control_pid);
  85         m->control_pid = 0;
  86 }
  87
  88 static void mount_parameters_done(MountParameters *p) {
  89         assert(p);
  90
  91         free(p->what);
  92         free(p->options);
  93         free(p->fstype);
  94
  95         p->what = p->options = p->fstype = NULL;
  96 }
  97
  98 static void mount_done(Unit *u) {
  99         Mount *m = MOUNT(u);
 100
 101         assert(m);
 102
 103         free(m->where);
 104         m->where = NULL;
 105
 106         mount_parameters_done(&m->parameters_etc_fstab);
 107         mount_parameters_done(&m->parameters_proc_self_mountinfo);
 108         mount_parameters_done(&m->parameters_fragment);
 109
 110         exec_context_done(&m->exec_context);
 111         exec_command_done_array(m->exec_command, _MOUNT_EXEC_COMMAND_MAX);
 112         m->control_command = NULL;
 113
 114         service_unwatch_control_pid(m);
 115
 116         unit_unwatch_timer(u, &m->timer_watch);
 117 }
 118
 119 static void mount_init(Unit *u) {
 120         Mount *m = MOUNT(u);
 121
 122         assert(u);
 123         assert(u->meta.load_state == UNIT_STUB);
 124
 125         m->timeout_usec = DEFAULT_TIMEOUT_USEC;
 126         exec_context_init(&m->exec_context);
 127
 128         /* We need to make sure that /bin/mount is always called in
 129          * the same process group as us, so that the autofs kernel
 130          * side doesn't send us another mount request while we are
 131          * already trying to comply its last one. */
 132         m->exec_context.no_setsid = true;
 133
 134         m->timer_watch.type = WATCH_INVALID;
 135 }
 136
 137 static int mount_notify_automount(Mount *m, int status) {
 138         Unit *p;
 139         char *k;
 140
 141         assert(m);
 142
 143         if (!(k = unit_name_change_suffix(UNIT(m)->meta.id, ".automount")))
 144                 return -ENOMEM;
 145
 146         p = manager_get_unit(UNIT(m)->meta.manager, k);
 147         free(k);
 148
 149         if (!p)
 150                 return 0;
 151
 152         return automount_send_ready(AUTOMOUNT(p), status);
 153 }
 154
 155 static int mount_add_node_links(Mount *m) {
 156         Unit *device;
 157         char *e;
 158         int r;
 159         const char *what;
 160
 161         assert(m);
 162
 163         /* Adds in links to the device that this node is based on */
 164
 165         if (m->parameters_fragment.what)
 166                 what = m->parameters_fragment.what;
 167         else if (m->parameters_etc_fstab.what)
 168                 what = m->parameters_etc_fstab.what;
 169         else
 170                 /* We observe kernel mounts only while they are live,
 171                  * hence don't create any links for them */
 172                 return 0;
 173
 174         if (!path_startswith(what, "/dev/"))
 175                 return 0;
 176
 177         if (!(e = unit_name_build_escape(what+1, NULL, ".device")))
 178                 return -ENOMEM;
 179
 180         r = manager_load_unit(UNIT(m)->meta.manager, e, NULL, &device);
 181         free(e);
 182
 183         if (r < 0)
 184                 return r;
 185
 186         if ((r = unit_add_dependency(UNIT(m), UNIT_AFTER, device)) < 0)
 187                 return r;
 188
 189         if ((r = unit_add_dependency(UNIT(m), UNIT_REQUIRES, device)) < 0)
 190                 return r;
 191
 192         if (UNIT(m)->meta.manager->running_as == MANAGER_INIT ||
 193             UNIT(m)->meta.manager->running_as == MANAGER_SYSTEM)
 194                 if ((r = unit_add_dependency(device, UNIT_WANTS, UNIT(m))) < 0)
 195                         return r;
 196
 197         return 0;
 198 }
 199
 200 static int mount_add_path_links(Mount *m) {
 201         Meta *other;
 202         int r;
 203
 204         assert(m);
 205
 206         /* Adds in link to other mount points, that might lie below or
 207          * above us in the hierarchy */
 208
 209         LIST_FOREACH(units_per_type, other, UNIT(m)->meta.manager->units_per_type[UNIT_MOUNT]) {
 210                 Mount *n;
 211
 212                 n = (Mount*) other;
 213
 214                 if (n == m)
 215                         continue;
 216
 217                 if (m->meta.load_state != UNIT_LOADED)
 218                         continue;
 219
 220                 if (path_startswith(m->where, n->where)) {
 221
 222                         if ((r = unit_add_dependency(UNIT(m), UNIT_AFTER, UNIT(other))) < 0)
 223                                 return r;
 224
 225                         if (n->from_etc_fstab || n->from_fragment)
 226                                 if ((r = unit_add_dependency(UNIT(m), UNIT_REQUIRES, UNIT(other))) < 0)
 227                                         return r;
 228
 229                 } else if (path_startswith(n->where, m->where)) {
 230
 231                         if ((r = unit_add_dependency(UNIT(m), UNIT_BEFORE, UNIT(other))) < 0)
 232                                 return r;
 233
 234                         if (m->from_etc_fstab || m->from_fragment)
 235                                 if ((r = unit_add_dependency(UNIT(other), UNIT_REQUIRES, UNIT(m))) < 0)
 236                                         return r;
 237                 }
 238         }
 239
 240         return 0;
 241 }
 242
 243 static bool mount_test_option(const char *haystack, const char *needle) {
 244         struct mntent me;
 245
 246         assert(needle);
 247
 248         /* Like glibc's hasmntopt(), but works on a string, not a
 249          * struct mntent */
 250
 251         if (!haystack)
 252                 return false;
 253
 254         zero(me);
 255         me.mnt_opts = (char*) haystack;
 256
 257         return !!hasmntopt(&me, needle);
 258 }
 259
 260 static int mount_add_target_links(Mount *m) {
 261         const char *target;
 262         MountParameters *p;
 263         Unit *u;
 264         int r;
 265         bool noauto;
 266         bool handle;
 267
 268         assert(m);
 269
 270         if (m->from_fragment)
 271                 p = &m->parameters_fragment;
 272         else if (m->from_etc_fstab)
 273                 p = &m->parameters_etc_fstab;
 274         else
 275                 return 0;
 276
 277         noauto = mount_test_option(p->options, MNTOPT_NOAUTO);
 278         handle = mount_test_option(p->options, "comment=systemd.mount");
 279
 280         if (noauto && !handle)
 281                 return 0;
 282
 283         if (mount_test_option(p->options, "_netdev") ||
 284             fstype_is_network(p->fstype))
 285                 target = SPECIAL_REMOTE_FS_TARGET;
 286         else
 287                 target = SPECIAL_LOCAL_FS_TARGET;
 288
 289         if ((r = manager_load_unit(UNIT(m)->meta.manager, target, NULL, &u)) < 0)
 290                 return r;
 291
 292         if (handle)
 293                 if ((r = unit_add_dependency(u, UNIT_WANTS, UNIT(m))) < 0)
 294                         return r;
 295
 296         return unit_add_dependency(UNIT(m), UNIT_BEFORE, u);
 297 }
 298
 299 static int mount_verify(Mount *m) {
 300         bool b;
 301         char *e;
 302         assert(m);
 303
 304         if (UNIT(m)->meta.load_state != UNIT_LOADED)
 305                 return 0;
 306
 307         if (!m->where) {
 308                 log_error("%s lacks Where setting. Refusing.", UNIT(m)->meta.id);
 309                 return -EINVAL;
 310         }
 311
 312         path_kill_slashes(m->where);
 313
 314         if (!(e = mount_name_from_where(m->where)))
 315                 return -ENOMEM;
 316
 317         b = unit_has_name(UNIT(m), e);
 318         free(e);
 319
 320         if (!b) {
 321                 log_error("%s's Where setting doesn't match unit name. Refusing.", UNIT(m)->meta.id);
 322                 return -EINVAL;
 323         }
 324
 325         return 0;
 326 }
 327
 328 static int mount_load(Unit *u) {
 329         Mount *m = MOUNT(u);
 330         int r;
 331
 332         assert(u);
 333         assert(u->meta.load_state == UNIT_STUB);
 334
 335         if ((r = unit_load_fragment_and_dropin_optional(u)) < 0)
 336                 return r;
 337
 338         /* This is a new unit? Then let's add in some extras */
 339         if (u->meta.load_state == UNIT_LOADED) {
 340
 341                 /* Minor validity checking */
 342                 if ((m->parameters_fragment.options || m->parameters_fragment.fstype) && !m->parameters_fragment.what)
 343                         return -EBADMSG;
 344
 345                 if (m->parameters_fragment.what)
 346                         m->from_fragment = true;
 347
 348                 if ((r = mount_add_node_links(MOUNT(u))) < 0)
 349                         return r;
 350
 351                 if ((r = mount_add_path_links(MOUNT(u))) < 0)
 352                         return r;
 353
 354                 if ((r = mount_add_target_links(MOUNT(u))) < 0)
 355                         return r;
 356
 357                 if ((r = unit_add_default_cgroup(u)) < 0)
 358                         return r;
 359         }
 360
 361         return mount_verify(m);
 362 }
 363
 364 static void mount_set_state(Mount *m, MountState state) {
 365         MountState old_state;
 366         assert(m);
 367
 368         old_state = m->state;
 369         m->state = state;
 370
 371         if (state != MOUNT_MOUNTING &&
 372             state != MOUNT_MOUNTING_DONE &&
 373             state != MOUNT_REMOUNTING &&
 374             state != MOUNT_UNMOUNTING &&
 375             state != MOUNT_MOUNTING_SIGTERM &&
 376             state != MOUNT_MOUNTING_SIGKILL &&
 377             state != MOUNT_UNMOUNTING_SIGTERM &&
 378             state != MOUNT_UNMOUNTING_SIGKILL &&
 379             state != MOUNT_REMOUNTING_SIGTERM &&
 380             state != MOUNT_REMOUNTING_SIGKILL) {
 381                 unit_unwatch_timer(UNIT(m), &m->timer_watch);
 382                 service_unwatch_control_pid(m);
 383                 m->control_command = NULL;
 384         }
 385
 386         if (state == MOUNT_MOUNTED ||
 387             state == MOUNT_REMOUNTING)
 388                 mount_notify_automount(m, 0);
 389         else if (state == MOUNT_DEAD ||
 390                  state == MOUNT_UNMOUNTING ||
 391                  state == MOUNT_MOUNTING_SIGTERM ||
 392                  state == MOUNT_MOUNTING_SIGKILL ||
 393                  state == MOUNT_REMOUNTING_SIGTERM ||
 394                  state == MOUNT_REMOUNTING_SIGKILL ||
 395                  state == MOUNT_UNMOUNTING_SIGTERM ||
 396                  state == MOUNT_UNMOUNTING_SIGKILL ||
 397                  state == MOUNT_MAINTAINANCE)
 398                 mount_notify_automount(m, -ENODEV);
 399
 400         if (state != old_state)
 401                 log_debug("%s changed %s → %s", UNIT(m)->meta.id, state_string_table[old_state], state_string_table[state]);
 402
 403         unit_notify(UNIT(m), state_translation_table[old_state], state_translation_table[state]);
 404 }
 405
 406 static int mount_coldplug(Unit *u) {
 407         Mount *m = MOUNT(u);
 408
 409         assert(m);
 410         assert(m->state == MOUNT_DEAD);
 411
 412         if (m->from_proc_self_mountinfo)
 413                 mount_set_state(m, MOUNT_MOUNTED);
 414
 415         return 0;
 416 }
 417
 418 static int mount_spawn(Mount *m, ExecCommand *c, pid_t *_pid) {
 419         pid_t pid;
 420         int r;
 421
 422         assert(m);
 423         assert(c);
 424         assert(_pid);
 425
 426         if ((r = unit_watch_timer(UNIT(m), m->timeout_usec, &m->timer_watch)) < 0)
 427                 goto fail;
 428
 429         if ((r = exec_spawn(c,
 430                             NULL,
 431                             &m->exec_context,
 432                             NULL, 0,
 433                             true,
 434                             true,
 435                             UNIT(m)->meta.manager->confirm_spawn,
 436                             UNIT(m)->meta.cgroup_bondings,
 437                             &pid)) < 0)
 438                 goto fail;
 439
 440         if ((r = unit_watch_pid(UNIT(m), pid)) < 0)
 441                 /* FIXME: we need to do something here */
 442                 goto fail;
 443
 444         *_pid = pid;
 445
 446         return 0;
 447
 448 fail:
 449         unit_unwatch_timer(UNIT(m), &m->timer_watch);
 450
 451         return r;
 452 }
 453
 454 static void mount_dump(Unit *u, FILE *f, const char *prefix) {
 455         Mount *m = MOUNT(u);
 456         MountParameters *p;
 457
 458         assert(m);
 459         assert(f);
 460
 461         if (m->from_proc_self_mountinfo)
 462                 p = &m->parameters_proc_self_mountinfo;
 463         else if (m->from_fragment)
 464                 p = &m->parameters_fragment;
 465         else
 466                 p = &m->parameters_etc_fstab;
 467
 468         fprintf(f,
 469                 "%sMount State: %s\n"
 470                 "%sWhere: %s\n"
 471                 "%sWhat: %s\n"
 472                 "%sFile System Type: %s\n"
 473                 "%sOptions: %s\n"
 474                 "%sFrom /etc/fstab: %s\n"
 475                 "%sFrom /proc/self/mountinfo: %s\n"
 476                 "%sFrom fragment: %s\n"
 477                 "%sKillMode: %s\n",
 478                 prefix, state_string_table[m->state],
 479                 prefix, m->where,
 480                 prefix, strna(p->what),
 481                 prefix, strna(p->fstype),
 482                 prefix, strna(p->options),
 483                 prefix, yes_no(m->from_etc_fstab),
 484                 prefix, yes_no(m->from_proc_self_mountinfo),
 485                 prefix, yes_no(m->from_fragment),
 486                 prefix, kill_mode_to_string(m->kill_mode));
 487
 488         if (m->control_pid > 0)
 489                 fprintf(f,
 490                         "%sControl PID: %llu\n",
 491                         prefix, (unsigned long long) m->control_pid);
 492
 493         exec_context_dump(&m->exec_context, f, prefix);
 494 }
 495
 496 static void mount_enter_dead(Mount *m, bool success) {
 497         assert(m);
 498
 499         if (!success)
 500                 m->failure = true;
 501
 502         mount_set_state(m, m->failure ? MOUNT_MAINTAINANCE : MOUNT_DEAD);
 503 }
 504
 505 static void mount_enter_mounted(Mount *m, bool success) {
 506         assert(m);
 507
 508         if (!success)
 509                 m->failure = true;
 510
 511         mount_set_state(m, MOUNT_MOUNTED);
 512 }
 513
 514 static void mount_enter_signal(Mount *m, MountState state, bool success) {
 515         int r;
 516         bool sent = false;
 517
 518         assert(m);
 519
 520         if (!success)
 521                 m->failure = true;
 522
 523         if (m->kill_mode != KILL_NONE) {
 524                 int sig = (state == MOUNT_MOUNTING_SIGTERM ||
 525                            state == MOUNT_UNMOUNTING_SIGTERM ||
 526                            state == MOUNT_REMOUNTING_SIGTERM) ? SIGTERM : SIGKILL;
 527
 528                 if (m->kill_mode == KILL_CONTROL_GROUP) {
 529
 530                         if ((r = cgroup_bonding_kill_list(UNIT(m)->meta.cgroup_bondings, sig)) < 0) {
 531                                 if (r != -EAGAIN && r != -ESRCH)
 532                                         goto fail;
 533                         } else
 534                                 sent = true;
 535                 }
 536
 537                 if (!sent && m->control_pid > 0)
 538                         if (kill(m->kill_mode == KILL_PROCESS ? m->control_pid : -m->control_pid, sig) < 0 && errno != ESRCH) {
 539                                 r = -errno;
 540                                 goto fail;
 541                         }
 542         }
 543
 544         if (sent) {
 545                 if ((r = unit_watch_timer(UNIT(m), m->timeout_usec, &m->timer_watch)) < 0)
 546                         goto fail;
 547
 548                 mount_set_state(m, state);
 549         } else if (state == MOUNT_REMOUNTING_SIGTERM || state == MOUNT_REMOUNTING_SIGKILL)
 550                 mount_enter_mounted(m, true);
 551         else
 552                 mount_enter_dead(m, true);
 553
 554         return;
 555
 556 fail:
 557         log_warning("%s failed to kill processes: %s", UNIT(m)->meta.id, strerror(-r));
 558
 559         if (state == MOUNT_REMOUNTING_SIGTERM || state == MOUNT_REMOUNTING_SIGKILL)
 560                 mount_enter_mounted(m, false);
 561         else
 562                 mount_enter_dead(m, false);
 563 }
 564
 565 static void mount_enter_unmounting(Mount *m, bool success) {
 566         ExecCommand *c;
 567         int r;
 568
 569         assert(m);
 570
 571         if (!success)
 572                 m->failure = true;
 573
 574         m->control_command = c = m->exec_command + MOUNT_EXEC_UNMOUNT;
 575
 576         if ((r = exec_command_set(
 577                              c,
 578                              "/bin/umount",
 579                              m->where,
 580                              NULL)) < 0)
 581                 goto fail;
 582
 583         service_unwatch_control_pid(m);
 584
 585         if ((r = mount_spawn(m, c, &m->control_pid)) < 0)
 586                 goto fail;
 587
 588         mount_set_state(m, MOUNT_UNMOUNTING);
 589
 590         return;
 591
 592 fail:
 593         log_warning("%s failed to run umount exectuable: %s", UNIT(m)->meta.id, strerror(-r));
 594         mount_enter_mounted(m, false);
 595 }
 596
 597 static void mount_enter_mounting(Mount *m) {
 598         ExecCommand *c;
 599         int r;
 600
 601         assert(m);
 602
 603         m->control_command = c = m->exec_command + MOUNT_EXEC_MOUNT;
 604
 605         if (m->from_fragment)
 606                 r = exec_command_set(
 607                                 c,
 608                                 "/bin/mount",
 609                                 m->parameters_fragment.what,
 610                                 m->where,
 611                                 "-t", m->parameters_fragment.fstype,
 612                                 m->parameters_fragment.options ? "-o" : NULL, m->parameters_fragment.options,
 613                                 NULL);
 614         else if (m->from_etc_fstab)
 615                 r = exec_command_set(
 616                                 c,
 617                                 "/bin/mount",
 618                                 m->where,
 619                                 NULL);
 620         else
 621                 r = -ENOENT;
 622
 623         if (r < 0)
 624                 goto fail;
 625
 626         service_unwatch_control_pid(m);
 627
 628         if ((r = mount_spawn(m, c, &m->control_pid)) < 0)
 629                 goto fail;
 630
 631         mount_set_state(m, MOUNT_MOUNTING);
 632
 633         return;
 634
 635 fail:
 636         log_warning("%s failed to run mount exectuable: %s", UNIT(m)->meta.id, strerror(-r));
 637         mount_enter_dead(m, false);
 638 }
 639
 640 static void mount_enter_mounting_done(Mount *m) {
 641         assert(m);
 642
 643         mount_set_state(m, MOUNT_MOUNTING_DONE);
 644 }
 645
 646 static void mount_enter_remounting(Mount *m, bool success) {
 647         ExecCommand *c;
 648         int r;
 649
 650         assert(m);
 651
 652         if (!success)
 653                 m->failure = true;
 654
 655         m->control_command = c = m->exec_command + MOUNT_EXEC_REMOUNT;
 656
 657         if (m->from_fragment) {
 658                 char *buf = NULL;
 659                 const char *o;
 660
 661                 if (m->parameters_fragment.options) {
 662                         if (!(buf = strappend("remount,", m->parameters_fragment.options))) {
 663                                 r = -ENOMEM;
 664                                 goto fail;
 665                         }
 666
 667                         o = buf;
 668                 } else
 669                         o = "remount";
 670
 671                 r = exec_command_set(
 672                                 c,
 673                                 "/bin/mount",
 674                                 m->parameters_fragment.what,
 675                                 m->where,
 676                                 "-t", m->parameters_fragment.fstype,
 677                                 "-o", o,
 678                                 NULL);
 679
 680                 free(buf);
 681         } else if (m->from_etc_fstab)
 682                 r = exec_command_set(
 683                                 c,
 684                                 "/bin/mount",
 685                                 m->where,
 686                                 "-o", "remount",
 687                                 NULL);
 688         else
 689                 r = -ENOENT;
 690
 691         if (r < 0) {
 692                 r = -ENOMEM;
 693                 goto fail;
 694         }
 695
 696         service_unwatch_control_pid(m);
 697
 698         if ((r = mount_spawn(m, c, &m->control_pid)) < 0)
 699                 goto fail;
 700
 701         mount_set_state(m, MOUNT_REMOUNTING);
 702
 703         return;
 704
 705 fail:
 706         mount_enter_mounted(m, false);
 707 }
 708
 709 static int mount_start(Unit *u) {
 710         Mount *m = MOUNT(u);
 711
 712         assert(m);
 713
 714         /* We cannot fulfill this request right now, try again later
 715          * please! */
 716         if (m->state == MOUNT_UNMOUNTING ||
 717             m->state == MOUNT_UNMOUNTING_SIGTERM ||
 718             m->state == MOUNT_UNMOUNTING_SIGKILL)
 719                 return -EAGAIN;
 720
 721         /* Already on it! */
 722         if (m->state == MOUNT_MOUNTING ||
 723             m->state == MOUNT_MOUNTING_SIGTERM ||
 724             m->state == MOUNT_MOUNTING_SIGKILL)
 725                 return 0;
 726
 727         assert(m->state == MOUNT_DEAD || m->state == MOUNT_MAINTAINANCE);
 728
 729         m->failure = false;
 730
 731         mount_enter_mounting(m);
 732         return 0;
 733 }
 734
 735 static int mount_stop(Unit *u) {
 736         Mount *m = MOUNT(u);
 737
 738         assert(m);
 739
 740         /* Cann't do this right now. */
 741         if (m->state == MOUNT_MOUNTING ||
 742             m->state == MOUNT_MOUNTING_DONE ||
 743             m->state == MOUNT_MOUNTING_SIGTERM ||
 744             m->state == MOUNT_MOUNTING_SIGKILL ||
 745             m->state == MOUNT_REMOUNTING ||
 746             m->state == MOUNT_REMOUNTING_SIGTERM ||
 747             m->state == MOUNT_REMOUNTING_SIGKILL)
 748                 return -EAGAIN;
 749
 750         /* Already on it */
 751         if (m->state == MOUNT_UNMOUNTING ||
 752             m->state == MOUNT_UNMOUNTING_SIGKILL ||
 753             m->state == MOUNT_UNMOUNTING_SIGTERM)
 754                 return 0;
 755
 756         assert(m->state == MOUNT_MOUNTED);
 757
 758         mount_enter_unmounting(m, true);
 759         return 0;
 760 }
 761
 762 static int mount_reload(Unit *u) {
 763         Mount *m = MOUNT(u);
 764
 765         assert(m);
 766
 767         if (m->state == MOUNT_MOUNTING_DONE)
 768                 return -EAGAIN;
 769
 770         assert(m->state == MOUNT_MOUNTED);
 771
 772         mount_enter_remounting(m, true);
 773         return 0;
 774 }
 775
 776 static UnitActiveState mount_active_state(Unit *u) {
 777         assert(u);
 778
 779         return state_translation_table[MOUNT(u)->state];
 780 }
 781
 782 static const char *mount_sub_state_to_string(Unit *u) {
 783         assert(u);
 784
 785         return state_string_table[MOUNT(u)->state];
 786 }
 787
 788 static void mount_sigchld_event(Unit *u, pid_t pid, int code, int status) {
 789         Mount *m = MOUNT(u);
 790         bool success;
 791
 792         assert(m);
 793         assert(pid >= 0);
 794
 795         success = code == CLD_EXITED && status == 0;
 796         m->failure = m->failure || !success;
 797
 798         assert(m->control_pid == pid);
 799         assert(m->control_command);
 800
 801         exec_status_fill(&m->control_command->exec_status, pid, code, status);
 802         m->control_pid = 0;
 803
 804         log_debug("%s control process exited, code=%s status=%i", u->meta.id, sigchld_code_to_string(code), status);
 805
 806         /* Note that mount(8) returning and the kernel sending us a
 807          * mount table change event might happen out-of-order. If an
 808          * operation succeed we assume the kernel will follow soon too
 809          * and already change into the resulting state.  If it fails
 810          * we check if the kernel still knows about the mount. and
 811          * change state accordingly. */
 812
 813         switch (m->state) {
 814
 815         case MOUNT_MOUNTING:
 816         case MOUNT_MOUNTING_DONE:
 817         case MOUNT_MOUNTING_SIGKILL:
 818         case MOUNT_MOUNTING_SIGTERM:
 819         case MOUNT_REMOUNTING:
 820         case MOUNT_REMOUNTING_SIGKILL:
 821         case MOUNT_REMOUNTING_SIGTERM:
 822
 823                 if (success && m->from_proc_self_mountinfo)
 824                         mount_enter_mounted(m, true);
 825                 else if (m->from_proc_self_mountinfo)
 826                         mount_enter_mounted(m, false);
 827                 else
 828                         mount_enter_dead(m, false);
 829                 break;
 830
 831         case MOUNT_UNMOUNTING:
 832         case MOUNT_UNMOUNTING_SIGKILL:
 833         case MOUNT_UNMOUNTING_SIGTERM:
 834
 835                 if (success)
 836                         mount_enter_dead(m, true);
 837                 else if (m->from_proc_self_mountinfo)
 838                         mount_enter_mounted(m, false);
 839                 else
 840                         mount_enter_dead(m, false);
 841                 break;
 842
 843         default:
 844                 assert_not_reached("Uh, control process died at wrong time.");
 845         }
 846 }
 847
 848 static void mount_timer_event(Unit *u, uint64_t elapsed, Watch *w) {
 849         Mount *m = MOUNT(u);
 850
 851         assert(m);
 852         assert(elapsed == 1);
 853         assert(w == &m->timer_watch);
 854
 855         switch (m->state) {
 856
 857         case MOUNT_MOUNTING:
 858         case MOUNT_MOUNTING_DONE:
 859                 log_warning("%s mounting timed out. Stopping.", u->meta.id);
 860                 mount_enter_signal(m, MOUNT_MOUNTING_SIGTERM, false);
 861                 break;
 862
 863         case MOUNT_REMOUNTING:
 864                 log_warning("%s remounting timed out. Stopping.", u->meta.id);
 865                 mount_enter_signal(m, MOUNT_REMOUNTING_SIGTERM, false);
 866                 break;
 867
 868         case MOUNT_UNMOUNTING:
 869                 log_warning("%s unmounting timed out. Stopping.", u->meta.id);
 870                 mount_enter_signal(m, MOUNT_UNMOUNTING_SIGTERM, false);
 871                 break;
 872
 873         case MOUNT_MOUNTING_SIGTERM:
 874                 log_warning("%s mounting timed out. Killing.", u->meta.id);
 875                 mount_enter_signal(m, MOUNT_MOUNTING_SIGKILL, false);
 876                 break;
 877
 878         case MOUNT_REMOUNTING_SIGTERM:
 879                 log_warning("%s remounting timed out. Killing.", u->meta.id);
 880                 mount_enter_signal(m, MOUNT_REMOUNTING_SIGKILL, false);
 881                 break;
 882
 883         case MOUNT_UNMOUNTING_SIGTERM:
 884                 log_warning("%s unmounting timed out. Killing.", u->meta.id);
 885                 mount_enter_signal(m, MOUNT_UNMOUNTING_SIGKILL, false);
 886                 break;
 887
 888         case MOUNT_MOUNTING_SIGKILL:
 889         case MOUNT_REMOUNTING_SIGKILL:
 890         case MOUNT_UNMOUNTING_SIGKILL:
 891                 log_warning("%s mount process still around after SIGKILL. Ignoring.", u->meta.id);
 892
 893                 if (m->from_proc_self_mountinfo)
 894                         mount_enter_mounted(m, false);
 895                 else
 896                         mount_enter_dead(m, false);
 897                 break;
 898
 899         default:
 900                 assert_not_reached("Timeout at wrong time.");
 901         }
 902 }
 903
 904 static int mount_add_one(
 905                 Manager *m,
 906                 const char *what,
 907                 const char *where,
 908                 const char *options,
 909                 const char *fstype,
 910                 bool from_proc_self_mountinfo,
 911                 bool set_flags) {
 912         int r;
 913         Unit *u;
 914         bool delete;
 915         char *e, *w = NULL, *o = NULL, *f = NULL;
 916         MountParameters *mp;
 917
 918         assert(m);
 919         assert(what);
 920         assert(where);
 921         assert(options);
 922         assert(fstype);
 923
 924         assert(!set_flags || from_proc_self_mountinfo);
 925
 926         /* Ignore API mount points. They should never be referenced in
 927          * dependencies ever. */
 928         if (mount_point_is_api(where))
 929                 return 0;
 930
 931         if (streq(fstype, "autofs"))
 932                 return 0;
 933
 934         /* probably some kind of swap, which we don't cover for now */
 935         if (where[0] != '/')
 936                 return 0;
 937
 938         e = mount_name_from_where(where);
 939
 940         if (!e)
 941                 return -ENOMEM;
 942
 943         if (!(u = manager_get_unit(m, e))) {
 944                 delete = true;
 945
 946                 if (!(u = unit_new(m))) {
 947                         free(e);
 948                         return -ENOMEM;
 949                 }
 950
 951                 r = unit_add_name(u, e);
 952                 free(e);
 953
 954                 if (r < 0)
 955                         goto fail;
 956
 957                 if (!(MOUNT(u)->where = strdup(where))) {
 958                             r = -ENOMEM;
 959                             goto fail;
 960                     }
 961
 962                 if ((r = unit_set_description(u, where)) < 0)
 963                         goto fail;
 964
 965                 unit_add_to_load_queue(u);
 966         } else {
 967                 delete = false;
 968                 free(e);
 969         }
 970
 971         if (!(w = strdup(what)) ||
 972             !(o = strdup(options)) ||
 973             !(f = strdup(fstype))) {
 974                 r = -ENOMEM;
 975                 goto fail;
 976         }
 977
 978         if (from_proc_self_mountinfo) {
 979                 mp = &MOUNT(u)->parameters_proc_self_mountinfo;
 980
 981                 if (set_flags) {
 982                         MOUNT(u)->is_mounted = true;
 983                         MOUNT(u)->just_mounted = !MOUNT(u)->from_proc_self_mountinfo;
 984                         MOUNT(u)->just_changed = !streq_ptr(MOUNT(u)->parameters_proc_self_mountinfo.options, o);
 985                 }
 986
 987                 MOUNT(u)->from_proc_self_mountinfo = true;
 988
 989         } else {
 990                 mp = &MOUNT(u)->parameters_etc_fstab;
 991
 992                 MOUNT(u)->from_etc_fstab = true;
 993         }
 994
 995         free(mp->what);
 996         mp->what = w;
 997
 998         free(mp->options);
 999         mp->options = o;
1000
1001         free(mp->fstype);
1002         mp->fstype = f;
1003
1004         unit_add_to_dbus_queue(u);
1005
1006         return 0;
1007
1008 fail:
1009         free(w);
1010         free(o);
1011         free(f);
1012
1013         if (delete && u)
1014                 unit_free(u);
1015
1016         return 0;
1017 }
1018
1019 static char *fstab_node_to_udev_node(char *p) {
1020         char *dn, *t;
1021         int r;
1022
1023         /* FIXME: to follow udev's logic 100% we need to leave valid
1024          * UTF8 chars unescaped */
1025
1026         if (startswith(p, "LABEL=")) {
1027
1028                 if (!(t = xescape(p+6, "/ ")))
1029                         return NULL;
1030
1031                 r = asprintf(&dn, "/dev/disk/by-label/%s", t);
1032                 free(t);
1033
1034                 if (r < 0)
1035                         return NULL;
1036
1037                 return dn;
1038         }
1039
1040         if (startswith(p, "UUID=")) {
1041
1042                 if (!(t = xescape(p+5, "/ ")))
1043                         return NULL;
1044
1045                 r = asprintf(&dn, "/dev/disk/by-uuid/%s", ascii_strlower(t));
1046                 free(t);
1047
1048                 if (r < 0)
1049                         return NULL;
1050
1051                 return dn;
1052         }
1053
1054         return strdup(p);
1055 }
1056
1057 static int mount_load_etc_fstab(Manager *m) {
1058         FILE *f;
1059         int r;
1060         struct mntent* me;
1061
1062         assert(m);
1063
1064         errno = 0;
1065         if (!(f = setmntent("/etc/fstab", "r")))
1066                 return -errno;
1067
1068         while ((me = getmntent(f))) {
1069                 char *where, *what;
1070
1071                 if (!(what = fstab_node_to_udev_node(me->mnt_fsname))) {
1072                         r = -ENOMEM;
1073                         goto finish;
1074                 }
1075
1076                 if (!(where = strdup(me->mnt_dir))) {
1077                         free(what);
1078                         r = -ENOMEM;
1079                         goto finish;
1080                 }
1081
1082                 if (what[0] == '/')
1083                         path_kill_slashes(what);
1084
1085                 if (where[0] == '/')
1086                         path_kill_slashes(where);
1087
1088                 r = mount_add_one(m, what, where, me->mnt_opts, me->mnt_type, false, false);
1089                 free(what);
1090                 free(where);
1091
1092                 if (r < 0)
1093                         goto finish;
1094         }
1095
1096         r = 0;
1097 finish:
1098
1099         endmntent(f);
1100         return r;
1101 }
1102
1103 static int mount_load_proc_self_mountinfo(Manager *m, bool set_flags) {
1104         int r;
1105         char *device, *path, *options, *fstype, *d, *p;
1106
1107         assert(m);
1108
1109         rewind(m->proc_self_mountinfo);
1110
1111         for (;;) {
1112                 int k;
1113
1114                 device = path = options = fstype = d = p = NULL;
1115
1116                 if ((k = fscanf(m->proc_self_mountinfo,
1117                                 "%*s "       /* (1) mount id */
1118                                 "%*s "       /* (2) parent id */
1119                                 "%*s "       /* (3) major:minor */
1120                                 "%*s "       /* (4) root */
1121                                 "%ms "       /* (5) mount point */
1122                                 "%ms"        /* (6) mount options */
1123                                 "%*[^-]"     /* (7) optional fields */
1124                                 "- "         /* (8) seperator */
1125                                 "%ms "       /* (9) file system type */
1126                                 "%ms"        /* (10) mount source */
1127                                 "%*[^\n]",   /* some rubbish at the end */
1128                                 &path,
1129                                 &options,
1130                                 &fstype,
1131                                 &device)) != 4) {
1132
1133                         if (k == EOF)
1134                                 break;
1135
1136                         r = -EBADMSG;
1137                         goto finish;
1138                 }
1139
1140                 if (!(d = cunescape(device)) ||
1141                     !(p = cunescape(path))) {
1142                         r = -ENOMEM;
1143                         goto finish;
1144                 }
1145
1146                 if ((r = mount_add_one(m, d, p, options, fstype, true, set_flags)) < 0)
1147                         goto finish;
1148
1149                 free(device);
1150                 free(path);
1151                 free(options);
1152                 free(fstype);
1153                 free(d);
1154                 free(p);
1155         }
1156
1157         r = 0;
1158
1159 finish:
1160         free(device);
1161         free(path);
1162         free(options);
1163         free(fstype);
1164         free(d);
1165         free(p);
1166
1167         return r;
1168 }
1169
1170 static void mount_shutdown(Manager *m) {
1171         assert(m);
1172
1173         if (m->proc_self_mountinfo)
1174                 fclose(m->proc_self_mountinfo);
1175 }
1176
1177 static int mount_enumerate(Manager *m) {
1178         int r;
1179         struct epoll_event ev;
1180         assert(m);
1181
1182         if (!(m->proc_self_mountinfo = fopen("/proc/self/mountinfo", "r")))
1183                 return -errno;
1184
1185         m->mount_watch.type = WATCH_MOUNT;
1186         m->mount_watch.fd = fileno(m->proc_self_mountinfo);
1187
1188         zero(ev);
1189         ev.events = EPOLLERR;
1190         ev.data.ptr = &m->mount_watch;
1191
1192         if (epoll_ctl(m->epoll_fd, EPOLL_CTL_ADD, m->mount_watch.fd, &ev) < 0)
1193                 return -errno;
1194
1195         if ((r = mount_load_etc_fstab(m)) < 0)
1196                 goto fail;
1197
1198         if ((r = mount_load_proc_self_mountinfo(m, false)) < 0)
1199                 goto fail;
1200
1201         return 0;
1202
1203 fail:
1204         mount_shutdown(m);
1205         return r;
1206 }
1207
1208 void mount_fd_event(Manager *m, int events) {
1209         Meta *meta;
1210         int r;
1211
1212         assert(m);
1213         assert(events == EPOLLERR);
1214
1215         /* The manager calls this for every fd event happening on the
1216          * /proc/self/mountinfo file, which informs us about mounting
1217          * table changes */
1218
1219         if ((r = mount_load_proc_self_mountinfo(m, true)) < 0) {
1220                 log_error("Failed to reread /proc/self/mountinfo: %s", strerror(-errno));
1221
1222                 /* Reset flags, just in case, for later calls */
1223                 LIST_FOREACH(units_per_type, meta, m->units_per_type[UNIT_MOUNT]) {
1224                         Mount *mount = (Mount*) meta;
1225
1226                         mount->is_mounted = mount->just_mounted = mount->just_changed = false;
1227                 }
1228
1229                 return;
1230         }
1231
1232         manager_dispatch_load_queue(m);
1233
1234         LIST_FOREACH(units_per_type, meta, m->units_per_type[UNIT_MOUNT]) {
1235                 Mount *mount = (Mount*) meta;
1236
1237                 if (!mount->is_mounted) {
1238                         /* This has just been unmounted. */
1239
1240                         mount->from_proc_self_mountinfo = false;
1241
1242                         switch (mount->state) {
1243
1244                         case MOUNT_MOUNTED:
1245                                 mount_enter_dead(mount, true);
1246                                 break;
1247
1248                         default:
1249                                 mount_set_state(mount, mount->state);
1250                                 break;
1251
1252                         }
1253
1254                 } else if (mount->just_mounted || mount->just_changed) {
1255
1256                         /* New or changed entrymount */
1257
1258                         switch (mount->state) {
1259
1260                         case MOUNT_DEAD:
1261                         case MOUNT_MAINTAINANCE:
1262                                 mount_enter_mounted(mount, true);
1263                                 break;
1264
1265                         case MOUNT_MOUNTING:
1266                                 mount_enter_mounting_done(mount);
1267                                 break;
1268
1269                         default:
1270                                 /* Nothing really changed, but let's
1271                                  * issue an notification call
1272                                  * nonetheless, in case somebody is
1273                                  * waiting for this. (e.g. file system
1274                                  * ro/rw remounts.) */
1275                                 mount_set_state(mount, mount->state);
1276                                 break;
1277                         }
1278                 }
1279
1280                 /* Reset the flags for later calls */
1281                 mount->is_mounted = mount->just_mounted = mount->just_changed = false;
1282         }
1283 }
1284
1285 int mount_path_is_mounted(Manager *m, const char* path) {
1286         char *t;
1287         int r;
1288
1289         assert(m);
1290         assert(path);
1291
1292         if (path[0] != '/')
1293                 return 1;
1294
1295         if (!(t = strdup(path)))
1296                 return -ENOMEM;
1297
1298         path_kill_slashes(t);
1299
1300         for (;;) {
1301                 char *e, *slash;
1302                 Unit *u;
1303
1304                 if (!(e = mount_name_from_where(t))) {
1305                         r = -ENOMEM;
1306                         goto finish;
1307                 }
1308
1309                 u = manager_get_unit(m, e);
1310                 free(e);
1311
1312                 if (u &&
1313                     (MOUNT(u)->from_etc_fstab || MOUNT(u)->from_fragment) &&
1314                     MOUNT(u)->state != MOUNT_MOUNTED) {
1315                         r = 0;
1316                         goto finish;
1317                 }
1318
1319                 assert_se(slash = strrchr(t, '/'));
1320
1321                 if (slash == t) {
1322                         r = 1;
1323                         goto finish;
1324                 }
1325
1326                 *slash = 0;
1327         }
1328
1329         r = 1;
1330
1331 finish:
1332         free(t);
1333         return r;
1334 }
1335
1336 const UnitVTable mount_vtable = {
1337         .suffix = ".mount",
1338
1339         .no_alias = true,
1340         .no_instances = true,
1341
1342         .init = mount_init,
1343         .load = mount_load,
1344         .done = mount_done,
1345
1346         .coldplug = mount_coldplug,
1347
1348         .dump = mount_dump,
1349
1350         .start = mount_start,
1351         .stop = mount_stop,
1352         .reload = mount_reload,
1353
1354         .active_state = mount_active_state,
1355         .sub_state_to_string = mount_sub_state_to_string,
1356
1357         .sigchld_event = mount_sigchld_event,
1358         .timer_event = mount_timer_event,
1359
1360         .enumerate = mount_enumerate,
1361         .shutdown = mount_shutdown
1362 };