/*** This file is part of systemd. Copyright 2010 Lennart Poettering systemd is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version. systemd is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details. You should have received a copy of the GNU Lesser General Public License along with systemd; If not, see . ***/ #include #include #include #include #include "sd-messages.h" #include "alloc-util.h" #include "dbus-mount.h" #include "escape.h" #include "exit-status.h" #include "formats-util.h" #include "fstab-util.h" #include "log.h" #include "manager.h" #include "mkdir.h" #include "mount-setup.h" #include "mount-util.h" #include "mount.h" #include "parse-util.h" #include "path-util.h" #include "process-util.h" #include "special.h" #include "string-table.h" #include "string-util.h" #include "strv.h" #include "unit-name.h" #include "unit.h" #define RETRY_UMOUNT_MAX 32 DEFINE_TRIVIAL_CLEANUP_FUNC(struct libmnt_table*, mnt_free_table); DEFINE_TRIVIAL_CLEANUP_FUNC(struct libmnt_iter*, mnt_free_iter); static const UnitActiveState state_translation_table[_MOUNT_STATE_MAX] = { [MOUNT_DEAD] = UNIT_INACTIVE, [MOUNT_MOUNTING] = UNIT_ACTIVATING, [MOUNT_MOUNTING_DONE] = UNIT_ACTIVE, [MOUNT_MOUNTED] = UNIT_ACTIVE, [MOUNT_REMOUNTING] = UNIT_RELOADING, [MOUNT_UNMOUNTING] = UNIT_DEACTIVATING, [MOUNT_MOUNTING_SIGTERM] = UNIT_DEACTIVATING, [MOUNT_MOUNTING_SIGKILL] = UNIT_DEACTIVATING, [MOUNT_REMOUNTING_SIGTERM] = UNIT_RELOADING, [MOUNT_REMOUNTING_SIGKILL] = UNIT_RELOADING, [MOUNT_UNMOUNTING_SIGTERM] = UNIT_DEACTIVATING, [MOUNT_UNMOUNTING_SIGKILL] = UNIT_DEACTIVATING, [MOUNT_FAILED] = UNIT_FAILED }; static int mount_dispatch_timer(sd_event_source *source, usec_t usec, void *userdata); static int mount_dispatch_io(sd_event_source *source, int fd, uint32_t revents, void *userdata); static bool mount_needs_network(const char *options, const char *fstype) { if (fstab_test_option(options, "_netdev\0")) return true; if (fstype && fstype_is_network(fstype)) return true; return false; } static bool mount_is_network(const MountParameters *p) { assert(p); return mount_needs_network(p->options, p->fstype); } static bool mount_is_loop(const MountParameters *p) { assert(p); if (fstab_test_option(p->options, "loop\0")) return true; return false; } static bool mount_is_bind(const MountParameters *p) { assert(p); if (fstab_test_option(p->options, "bind\0" "rbind\0")) return true; if (p->fstype && STR_IN_SET(p->fstype, "bind", "rbind")) return true; return false; } static bool mount_is_auto(const MountParameters *p) { assert(p); return !fstab_test_option(p->options, "noauto\0"); } static bool mount_is_automount(const MountParameters *p) { assert(p); return fstab_test_option(p->options, "comment=systemd.automount\0" "x-systemd.automount\0"); } static bool mount_state_active(MountState state) { return IN_SET(state, MOUNT_MOUNTING, MOUNT_MOUNTING_DONE, MOUNT_REMOUNTING, MOUNT_UNMOUNTING, MOUNT_MOUNTING_SIGTERM, MOUNT_MOUNTING_SIGKILL, MOUNT_UNMOUNTING_SIGTERM, MOUNT_UNMOUNTING_SIGKILL, MOUNT_REMOUNTING_SIGTERM, MOUNT_REMOUNTING_SIGKILL); } static bool needs_quota(const MountParameters *p) { assert(p); /* Quotas are not enabled on network filesystems, * but we want them, for example, on storage connected via iscsi */ if (p->fstype && fstype_is_network(p->fstype)) return false; if (mount_is_bind(p)) return false; return fstab_test_option(p->options, "usrquota\0" "grpquota\0" "quota\0" "usrjquota\0" "grpjquota\0"); } static void mount_init(Unit *u) { Mount *m = MOUNT(u); assert(u); assert(u->load_state == UNIT_STUB); m->timeout_usec = u->manager->default_timeout_start_usec; m->directory_mode = 0755; if (unit_has_name(u, "-.mount")) { /* Don't allow start/stop for root directory */ u->refuse_manual_start = true; u->refuse_manual_stop = true; } else { /* The stdio/kmsg bridge socket is on /, in order to avoid a * dep loop, don't use kmsg logging for -.mount */ m->exec_context.std_output = u->manager->default_std_output; m->exec_context.std_error = u->manager->default_std_error; } /* We need to make sure that /usr/bin/mount is always called * in the same process group as us, so that the autofs kernel * side doesn't send us another mount request while we are * already trying to comply its last one. */ m->exec_context.same_pgrp = true; m->control_command_id = _MOUNT_EXEC_COMMAND_INVALID; u->ignore_on_isolate = true; } static int mount_arm_timer(Mount *m, usec_t usec) { int r; assert(m); if (m->timer_event_source) { r = sd_event_source_set_time(m->timer_event_source, usec); if (r < 0) return r; return sd_event_source_set_enabled(m->timer_event_source, SD_EVENT_ONESHOT); } if (usec == USEC_INFINITY) return 0; r = sd_event_add_time( UNIT(m)->manager->event, &m->timer_event_source, CLOCK_MONOTONIC, usec, 0, mount_dispatch_timer, m); if (r < 0) return r; (void) sd_event_source_set_description(m->timer_event_source, "mount-timer"); return 0; } static void mount_unwatch_control_pid(Mount *m) { assert(m); if (m->control_pid <= 0) return; unit_unwatch_pid(UNIT(m), m->control_pid); m->control_pid = 0; } static void mount_parameters_done(MountParameters *p) { assert(p); free(p->what); free(p->options); free(p->fstype); p->what = p->options = p->fstype = NULL; } static void mount_done(Unit *u) { Mount *m = MOUNT(u); assert(m); m->where = mfree(m->where); mount_parameters_done(&m->parameters_proc_self_mountinfo); mount_parameters_done(&m->parameters_fragment); m->exec_runtime = exec_runtime_unref(m->exec_runtime); exec_command_done_array(m->exec_command, _MOUNT_EXEC_COMMAND_MAX); m->control_command = NULL; dynamic_creds_unref(&m->dynamic_creds); mount_unwatch_control_pid(m); m->timer_event_source = sd_event_source_unref(m->timer_event_source); } _pure_ static MountParameters* get_mount_parameters_fragment(Mount *m) { assert(m); if (m->from_fragment) return &m->parameters_fragment; return NULL; } _pure_ static MountParameters* get_mount_parameters(Mount *m) { assert(m); if (m->from_proc_self_mountinfo) return &m->parameters_proc_self_mountinfo; return get_mount_parameters_fragment(m); } static int mount_add_mount_links(Mount *m) { _cleanup_free_ char *parent = NULL; MountParameters *pm; Unit *other; Iterator i; Set *s; int r; assert(m); if (!path_equal(m->where, "/")) { /* Adds in links to other mount points that might lie further * up in the hierarchy */ parent = dirname_malloc(m->where); if (!parent) return -ENOMEM; r = unit_require_mounts_for(UNIT(m), parent); if (r < 0) return r; } /* Adds in links to other mount points that might be needed * for the source path (if this is a bind mount or a loop mount) to be * available. */ pm = get_mount_parameters_fragment(m); if (pm && pm->what && path_is_absolute(pm->what) && (mount_is_bind(pm) || mount_is_loop(pm) || !mount_is_network(pm))) { r = unit_require_mounts_for(UNIT(m), pm->what); if (r < 0) return r; } /* Adds in links to other units that use this path or paths * further down in the hierarchy */ s = manager_get_units_requiring_mounts_for(UNIT(m)->manager, m->where); SET_FOREACH(other, s, i) { if (other->load_state != UNIT_LOADED) continue; if (other == UNIT(m)) continue; r = unit_add_dependency(other, UNIT_AFTER, UNIT(m), true); if (r < 0) return r; if (UNIT(m)->fragment_path) { /* If we have fragment configuration, then make this dependency required */ r = unit_add_dependency(other, UNIT_REQUIRES, UNIT(m), true); if (r < 0) return r; } } return 0; } static int mount_add_device_links(Mount *m) { MountParameters *p; bool device_wants_mount = false; int r; assert(m); p = get_mount_parameters(m); if (!p) return 0; if (!p->what) return 0; if (mount_is_bind(p)) return 0; if (!is_device_path(p->what)) return 0; /* /dev/root is a really weird thing, it's not a real device, * but just a path the kernel exports for the root file system * specified on the kernel command line. Ignore it here. */ if (path_equal(p->what, "/dev/root")) return 0; if (path_equal(m->where, "/")) return 0; if (mount_is_auto(p) && !mount_is_automount(p) && MANAGER_IS_SYSTEM(UNIT(m)->manager)) device_wants_mount = true; r = unit_add_node_link(UNIT(m), p->what, device_wants_mount, m->from_fragment ? UNIT_BINDS_TO : UNIT_REQUIRES); if (r < 0) return r; return 0; } static int mount_add_quota_links(Mount *m) { int r; MountParameters *p; assert(m); if (!MANAGER_IS_SYSTEM(UNIT(m)->manager)) return 0; p = get_mount_parameters_fragment(m); if (!p) return 0; if (!needs_quota(p)) return 0; r = unit_add_two_dependencies_by_name(UNIT(m), UNIT_BEFORE, UNIT_WANTS, SPECIAL_QUOTACHECK_SERVICE, NULL, true); if (r < 0) return r; r = unit_add_two_dependencies_by_name(UNIT(m), UNIT_BEFORE, UNIT_WANTS, SPECIAL_QUOTAON_SERVICE, NULL, true); if (r < 0) return r; return 0; } static bool should_umount(Mount *m) { MountParameters *p; if (PATH_IN_SET(m->where, "/", "/usr") || path_startswith(m->where, "/run/initramfs")) return false; p = get_mount_parameters(m); if (p && fstab_test_option(p->options, "x-initrd.mount\0") && !in_initrd()) return false; return true; } static int mount_add_default_dependencies(Mount *m) { MountParameters *p; const char *after; int r; assert(m); if (!UNIT(m)->default_dependencies) return 0; if (!MANAGER_IS_SYSTEM(UNIT(m)->manager)) return 0; /* We do not add any default dependencies to /, /usr or * /run/initramfs/, since they are guaranteed to stay * mounted the whole time, since our system is on it. * Also, don't bother with anything mounted below virtual * file systems, it's also going to be virtual, and hence * not worth the effort. */ if (PATH_IN_SET(m->where, "/", "/usr") || path_startswith(m->where, "/run/initramfs") || path_startswith(m->where, "/proc") || path_startswith(m->where, "/sys") || path_startswith(m->where, "/dev")) return 0; p = get_mount_parameters(m); if (!p) return 0; if (mount_is_network(p)) { /* We order ourselves after network.target. This is * primarily useful at shutdown: services that take * down the network should order themselves before * network.target, so that they are shut down only * after this mount unit is stopped. */ r = unit_add_dependency_by_name(UNIT(m), UNIT_AFTER, SPECIAL_NETWORK_TARGET, NULL, true); if (r < 0) return r; /* We pull in network-online.target, and order * ourselves after it. This is useful at start-up to * actively pull in tools that want to be started * before we start mounting network file systems, and * whose purpose it is to delay this until the network * is "up". */ r = unit_add_two_dependencies_by_name(UNIT(m), UNIT_WANTS, UNIT_AFTER, SPECIAL_NETWORK_ONLINE_TARGET, NULL, true); if (r < 0) return r; after = SPECIAL_REMOTE_FS_PRE_TARGET; } else after = SPECIAL_LOCAL_FS_PRE_TARGET; r = unit_add_dependency_by_name(UNIT(m), UNIT_AFTER, after, NULL, true); if (r < 0) return r; if (should_umount(m)) { r = unit_add_two_dependencies_by_name(UNIT(m), UNIT_BEFORE, UNIT_CONFLICTS, SPECIAL_UMOUNT_TARGET, NULL, true); if (r < 0) return r; } return 0; } static int mount_verify(Mount *m) { _cleanup_free_ char *e = NULL; MountParameters *p; int r; assert(m); if (UNIT(m)->load_state != UNIT_LOADED) return 0; if (!m->from_fragment && !m->from_proc_self_mountinfo) return -ENOENT; r = unit_name_from_path(m->where, ".mount", &e); if (r < 0) return log_unit_error_errno(UNIT(m), r, "Failed to generate unit name from mount path: %m"); if (!unit_has_name(UNIT(m), e)) { log_unit_error(UNIT(m), "Where= setting doesn't match unit name. Refusing."); return -EINVAL; } if (mount_point_is_api(m->where) || mount_point_ignore(m->where)) { log_unit_error(UNIT(m), "Cannot create mount unit for API file system %s. Refusing.", m->where); return -EINVAL; } p = get_mount_parameters_fragment(m); if (p && !p->what) { log_unit_error(UNIT(m), "What= setting is missing. Refusing."); return -EBADMSG; } if (m->exec_context.pam_name && m->kill_context.kill_mode != KILL_CONTROL_GROUP) { log_unit_error(UNIT(m), "Unit has PAM enabled. Kill mode must be set to control-group'. Refusing."); return -EINVAL; } return 0; } static int mount_add_extras(Mount *m) { Unit *u = UNIT(m); int r; assert(m); if (u->fragment_path) m->from_fragment = true; if (!m->where) { r = unit_name_to_path(u->id, &m->where); if (r < 0) return r; } path_kill_slashes(m->where); if (!u->description) { r = unit_set_description(u, m->where); if (r < 0) return r; } r = mount_add_device_links(m); if (r < 0) return r; r = mount_add_mount_links(m); if (r < 0) return r; r = mount_add_quota_links(m); if (r < 0) return r; r = unit_patch_contexts(u); if (r < 0) return r; r = unit_add_exec_dependencies(u, &m->exec_context); if (r < 0) return r; r = unit_set_default_slice(u); if (r < 0) return r; r = mount_add_default_dependencies(m); if (r < 0) return r; return 0; } static int mount_load(Unit *u) { Mount *m = MOUNT(u); int r; assert(u); assert(u->load_state == UNIT_STUB); if (m->from_proc_self_mountinfo) r = unit_load_fragment_and_dropin_optional(u); else r = unit_load_fragment_and_dropin(u); if (r < 0) return r; /* This is a new unit? Then let's add in some extras */ if (u->load_state == UNIT_LOADED) { r = mount_add_extras(m); if (r < 0) return r; } return mount_verify(m); } static void mount_set_state(Mount *m, MountState state) { MountState old_state; assert(m); old_state = m->state; m->state = state; if (!mount_state_active(state)) { m->timer_event_source = sd_event_source_unref(m->timer_event_source); mount_unwatch_control_pid(m); m->control_command = NULL; m->control_command_id = _MOUNT_EXEC_COMMAND_INVALID; } if (state != old_state) log_unit_debug(UNIT(m), "Changed %s -> %s", mount_state_to_string(old_state), mount_state_to_string(state)); unit_notify(UNIT(m), state_translation_table[old_state], state_translation_table[state], m->reload_result == MOUNT_SUCCESS); m->reload_result = MOUNT_SUCCESS; } static int mount_coldplug(Unit *u) { Mount *m = MOUNT(u); MountState new_state = MOUNT_DEAD; int r; assert(m); assert(m->state == MOUNT_DEAD); if (m->deserialized_state != m->state) new_state = m->deserialized_state; else if (m->from_proc_self_mountinfo) new_state = MOUNT_MOUNTED; if (new_state == m->state) return 0; if (m->control_pid > 0 && pid_is_unwaited(m->control_pid) && mount_state_active(new_state)) { r = unit_watch_pid(UNIT(m), m->control_pid); if (r < 0) return r; r = mount_arm_timer(m, usec_add(u->state_change_timestamp.monotonic, m->timeout_usec)); if (r < 0) return r; } if (!IN_SET(new_state, MOUNT_DEAD, MOUNT_FAILED)) (void) unit_setup_dynamic_creds(u); mount_set_state(m, new_state); return 0; } static void mount_dump(Unit *u, FILE *f, const char *prefix) { Mount *m = MOUNT(u); MountParameters *p; assert(m); assert(f); p = get_mount_parameters(m); fprintf(f, "%sMount State: %s\n" "%sResult: %s\n" "%sWhere: %s\n" "%sWhat: %s\n" "%sFile System Type: %s\n" "%sOptions: %s\n" "%sFrom /proc/self/mountinfo: %s\n" "%sFrom fragment: %s\n" "%sDirectoryMode: %04o\n", prefix, mount_state_to_string(m->state), prefix, mount_result_to_string(m->result), prefix, m->where, prefix, p ? strna(p->what) : "n/a", prefix, p ? strna(p->fstype) : "n/a", prefix, p ? strna(p->options) : "n/a", prefix, yes_no(m->from_proc_self_mountinfo), prefix, yes_no(m->from_fragment), prefix, m->directory_mode); if (m->control_pid > 0) fprintf(f, "%sControl PID: "PID_FMT"\n", prefix, m->control_pid); exec_context_dump(&m->exec_context, f, prefix); kill_context_dump(&m->kill_context, f, prefix); } static int mount_spawn(Mount *m, ExecCommand *c, pid_t *_pid) { pid_t pid; int r; ExecParameters exec_params = { .apply_permissions = true, .apply_chroot = true, .apply_tty_stdin = true, .stdin_fd = -1, .stdout_fd = -1, .stderr_fd = -1, }; assert(m); assert(c); assert(_pid); (void) unit_realize_cgroup(UNIT(m)); if (m->reset_cpu_usage) { (void) unit_reset_cpu_usage(UNIT(m)); m->reset_cpu_usage = false; } r = unit_setup_exec_runtime(UNIT(m)); if (r < 0) return r; r = unit_setup_dynamic_creds(UNIT(m)); if (r < 0) return r; r = mount_arm_timer(m, usec_add(now(CLOCK_MONOTONIC), m->timeout_usec)); if (r < 0) return r; exec_params.environment = UNIT(m)->manager->environment; exec_params.confirm_spawn = UNIT(m)->manager->confirm_spawn; exec_params.cgroup_supported = UNIT(m)->manager->cgroup_supported; exec_params.cgroup_path = UNIT(m)->cgroup_path; exec_params.cgroup_delegate = m->cgroup_context.delegate; exec_params.runtime_prefix = manager_get_runtime_prefix(UNIT(m)->manager); r = exec_spawn(UNIT(m), c, &m->exec_context, &exec_params, m->exec_runtime, &m->dynamic_creds, &pid); if (r < 0) return r; r = unit_watch_pid(UNIT(m), pid); if (r < 0) /* FIXME: we need to do something here */ return r; *_pid = pid; return 0; } static void mount_enter_dead(Mount *m, MountResult f) { assert(m); if (f != MOUNT_SUCCESS) m->result = f; mount_set_state(m, m->result != MOUNT_SUCCESS ? MOUNT_FAILED : MOUNT_DEAD); exec_runtime_destroy(m->exec_runtime); m->exec_runtime = exec_runtime_unref(m->exec_runtime); exec_context_destroy_runtime_directory(&m->exec_context, manager_get_runtime_prefix(UNIT(m)->manager)); dynamic_creds_destroy(&m->dynamic_creds); } static void mount_enter_mounted(Mount *m, MountResult f) { assert(m); if (f != MOUNT_SUCCESS) m->result = f; mount_set_state(m, MOUNT_MOUNTED); } static void mount_enter_signal(Mount *m, MountState state, MountResult f) { int r; assert(m); if (f != MOUNT_SUCCESS) m->result = f; r = unit_kill_context( UNIT(m), &m->kill_context, (state != MOUNT_MOUNTING_SIGTERM && state != MOUNT_UNMOUNTING_SIGTERM && state != MOUNT_REMOUNTING_SIGTERM) ? KILL_KILL : KILL_TERMINATE, -1, m->control_pid, false); if (r < 0) goto fail; if (r > 0) { r = mount_arm_timer(m, usec_add(now(CLOCK_MONOTONIC), m->timeout_usec)); if (r < 0) goto fail; mount_set_state(m, state); } else if (state == MOUNT_REMOUNTING_SIGTERM) mount_enter_signal(m, MOUNT_REMOUNTING_SIGKILL, MOUNT_SUCCESS); else if (state == MOUNT_REMOUNTING_SIGKILL) mount_enter_mounted(m, MOUNT_SUCCESS); else if (state == MOUNT_MOUNTING_SIGTERM) mount_enter_signal(m, MOUNT_MOUNTING_SIGKILL, MOUNT_SUCCESS); else if (state == MOUNT_UNMOUNTING_SIGTERM) mount_enter_signal(m, MOUNT_UNMOUNTING_SIGKILL, MOUNT_SUCCESS); else mount_enter_dead(m, MOUNT_SUCCESS); return; fail: log_unit_warning_errno(UNIT(m), r, "Failed to kill processes: %m"); if (state == MOUNT_REMOUNTING_SIGTERM || state == MOUNT_REMOUNTING_SIGKILL) mount_enter_mounted(m, MOUNT_FAILURE_RESOURCES); else mount_enter_dead(m, MOUNT_FAILURE_RESOURCES); } static void mount_enter_unmounting(Mount *m) { int r; assert(m); /* Start counting our attempts */ if (!IN_SET(m->state, MOUNT_UNMOUNTING, MOUNT_UNMOUNTING_SIGTERM, MOUNT_UNMOUNTING_SIGKILL)) m->n_retry_umount = 0; m->control_command_id = MOUNT_EXEC_UNMOUNT; m->control_command = m->exec_command + MOUNT_EXEC_UNMOUNT; r = exec_command_set(m->control_command, UMOUNT_PATH, m->where, NULL); if (r < 0) goto fail; mount_unwatch_control_pid(m); r = mount_spawn(m, m->control_command, &m->control_pid); if (r < 0) goto fail; mount_set_state(m, MOUNT_UNMOUNTING); return; fail: log_unit_warning_errno(UNIT(m), r, "Failed to run 'umount' task: %m"); mount_enter_mounted(m, MOUNT_FAILURE_RESOURCES); } static void mount_enter_mounting(Mount *m) { int r; MountParameters *p; assert(m); m->control_command_id = MOUNT_EXEC_MOUNT; m->control_command = m->exec_command + MOUNT_EXEC_MOUNT; r = unit_fail_if_symlink(UNIT(m), m->where); if (r < 0) goto fail; (void) mkdir_p_label(m->where, m->directory_mode); unit_warn_if_dir_nonempty(UNIT(m), m->where); /* Create the source directory for bind-mounts if needed */ p = get_mount_parameters_fragment(m); if (p && mount_is_bind(p)) (void) mkdir_p_label(p->what, m->directory_mode); if (p) { _cleanup_free_ char *opts = NULL; r = fstab_filter_options(p->options, "nofail\0" "noauto\0" "auto\0", NULL, NULL, &opts); if (r < 0) goto fail; r = exec_command_set(m->control_command, MOUNT_PATH, p->what, m->where, NULL); if (r >= 0 && m->sloppy_options) r = exec_command_append(m->control_command, "-s", NULL); if (r >= 0 && p->fstype) r = exec_command_append(m->control_command, "-t", p->fstype, NULL); if (r >= 0 && !isempty(opts)) r = exec_command_append(m->control_command, "-o", opts, NULL); } else r = -ENOENT; if (r < 0) goto fail; mount_unwatch_control_pid(m); r = mount_spawn(m, m->control_command, &m->control_pid); if (r < 0) goto fail; mount_set_state(m, MOUNT_MOUNTING); return; fail: log_unit_warning_errno(UNIT(m), r, "Failed to run 'mount' task: %m"); mount_enter_dead(m, MOUNT_FAILURE_RESOURCES); } static void mount_enter_remounting(Mount *m) { int r; MountParameters *p; assert(m); m->control_command_id = MOUNT_EXEC_REMOUNT; m->control_command = m->exec_command + MOUNT_EXEC_REMOUNT; p = get_mount_parameters_fragment(m); if (p) { const char *o; if (p->options) o = strjoina("remount,", p->options); else o = "remount"; r = exec_command_set(m->control_command, MOUNT_PATH, p->what, m->where, "-o", o, NULL); if (r >= 0 && m->sloppy_options) r = exec_command_append(m->control_command, "-s", NULL); if (r >= 0 && p->fstype) r = exec_command_append(m->control_command, "-t", p->fstype, NULL); } else r = -ENOENT; if (r < 0) goto fail; mount_unwatch_control_pid(m); r = mount_spawn(m, m->control_command, &m->control_pid); if (r < 0) goto fail; mount_set_state(m, MOUNT_REMOUNTING); return; fail: log_unit_warning_errno(UNIT(m), r, "Failed to run 'remount' task: %m"); m->reload_result = MOUNT_FAILURE_RESOURCES; mount_enter_mounted(m, MOUNT_SUCCESS); } static int mount_start(Unit *u) { Mount *m = MOUNT(u); int r; assert(m); /* We cannot fulfill this request right now, try again later * please! */ if (m->state == MOUNT_UNMOUNTING || m->state == MOUNT_UNMOUNTING_SIGTERM || m->state == MOUNT_UNMOUNTING_SIGKILL || m->state == MOUNT_MOUNTING_SIGTERM || m->state == MOUNT_MOUNTING_SIGKILL) return -EAGAIN; /* Already on it! */ if (m->state == MOUNT_MOUNTING) return 0; assert(m->state == MOUNT_DEAD || m->state == MOUNT_FAILED); r = unit_start_limit_test(u); if (r < 0) { mount_enter_dead(m, MOUNT_FAILURE_START_LIMIT_HIT); return r; } m->result = MOUNT_SUCCESS; m->reload_result = MOUNT_SUCCESS; m->reset_cpu_usage = true; mount_enter_mounting(m); return 1; } static int mount_stop(Unit *u) { Mount *m = MOUNT(u); assert(m); /* Already on it */ if (m->state == MOUNT_UNMOUNTING || m->state == MOUNT_UNMOUNTING_SIGKILL || m->state == MOUNT_UNMOUNTING_SIGTERM || m->state == MOUNT_MOUNTING_SIGTERM || m->state == MOUNT_MOUNTING_SIGKILL) return 0; assert(m->state == MOUNT_MOUNTING || m->state == MOUNT_MOUNTING_DONE || m->state == MOUNT_MOUNTED || m->state == MOUNT_REMOUNTING || m->state == MOUNT_REMOUNTING_SIGTERM || m->state == MOUNT_REMOUNTING_SIGKILL); mount_enter_unmounting(m); return 1; } static int mount_reload(Unit *u) { Mount *m = MOUNT(u); assert(m); if (m->state == MOUNT_MOUNTING_DONE) return -EAGAIN; assert(m->state == MOUNT_MOUNTED); mount_enter_remounting(m); return 1; } static int mount_serialize(Unit *u, FILE *f, FDSet *fds) { Mount *m = MOUNT(u); assert(m); assert(f); assert(fds); unit_serialize_item(u, f, "state", mount_state_to_string(m->state)); unit_serialize_item(u, f, "result", mount_result_to_string(m->result)); unit_serialize_item(u, f, "reload-result", mount_result_to_string(m->reload_result)); if (m->control_pid > 0) unit_serialize_item_format(u, f, "control-pid", PID_FMT, m->control_pid); if (m->control_command_id >= 0) unit_serialize_item(u, f, "control-command", mount_exec_command_to_string(m->control_command_id)); return 0; } static int mount_deserialize_item(Unit *u, const char *key, const char *value, FDSet *fds) { Mount *m = MOUNT(u); assert(u); assert(key); assert(value); assert(fds); if (streq(key, "state")) { MountState state; if ((state = mount_state_from_string(value)) < 0) log_unit_debug(u, "Failed to parse state value: %s", value); else m->deserialized_state = state; } else if (streq(key, "result")) { MountResult f; f = mount_result_from_string(value); if (f < 0) log_unit_debug(u, "Failed to parse result value: %s", value); else if (f != MOUNT_SUCCESS) m->result = f; } else if (streq(key, "reload-result")) { MountResult f; f = mount_result_from_string(value); if (f < 0) log_unit_debug(u, "Failed to parse reload result value: %s", value); else if (f != MOUNT_SUCCESS) m->reload_result = f; } else if (streq(key, "control-pid")) { pid_t pid; if (parse_pid(value, &pid) < 0) log_unit_debug(u, "Failed to parse control-pid value: %s", value); else m->control_pid = pid; } else if (streq(key, "control-command")) { MountExecCommand id; id = mount_exec_command_from_string(value); if (id < 0) log_unit_debug(u, "Failed to parse exec-command value: %s", value); else { m->control_command_id = id; m->control_command = m->exec_command + id; } } else log_unit_debug(u, "Unknown serialization key: %s", key); return 0; } _pure_ static UnitActiveState mount_active_state(Unit *u) { assert(u); return state_translation_table[MOUNT(u)->state]; } _pure_ static const char *mount_sub_state_to_string(Unit *u) { assert(u); return mount_state_to_string(MOUNT(u)->state); } _pure_ static bool mount_check_gc(Unit *u) { Mount *m = MOUNT(u); assert(m); return m->from_proc_self_mountinfo; } static void mount_sigchld_event(Unit *u, pid_t pid, int code, int status) { Mount *m = MOUNT(u); MountResult f; assert(m); assert(pid >= 0); if (pid != m->control_pid) return; m->control_pid = 0; if (is_clean_exit(code, status, NULL)) f = MOUNT_SUCCESS; else if (code == CLD_EXITED) f = MOUNT_FAILURE_EXIT_CODE; else if (code == CLD_KILLED) f = MOUNT_FAILURE_SIGNAL; else if (code == CLD_DUMPED) f = MOUNT_FAILURE_CORE_DUMP; else assert_not_reached("Unknown code"); if (f != MOUNT_SUCCESS) m->result = f; if (m->control_command) { exec_status_exit(&m->control_command->exec_status, &m->exec_context, pid, code, status); m->control_command = NULL; m->control_command_id = _MOUNT_EXEC_COMMAND_INVALID; } log_unit_full(u, f == MOUNT_SUCCESS ? LOG_DEBUG : LOG_NOTICE, 0, "Mount process exited, code=%s status=%i", sigchld_code_to_string(code), status); /* Note that mount(8) returning and the kernel sending us a * mount table change event might happen out-of-order. If an * operation succeed we assume the kernel will follow soon too * and already change into the resulting state. If it fails * we check if the kernel still knows about the mount. and * change state accordingly. */ switch (m->state) { case MOUNT_MOUNTING: case MOUNT_MOUNTING_DONE: case MOUNT_MOUNTING_SIGKILL: case MOUNT_MOUNTING_SIGTERM: if (f == MOUNT_SUCCESS) mount_enter_mounted(m, f); else if (m->from_proc_self_mountinfo) mount_enter_mounted(m, f); else mount_enter_dead(m, f); break; case MOUNT_REMOUNTING: case MOUNT_REMOUNTING_SIGKILL: case MOUNT_REMOUNTING_SIGTERM: m->reload_result = f; if (m->from_proc_self_mountinfo) mount_enter_mounted(m, MOUNT_SUCCESS); else mount_enter_dead(m, MOUNT_SUCCESS); break; case MOUNT_UNMOUNTING: case MOUNT_UNMOUNTING_SIGKILL: case MOUNT_UNMOUNTING_SIGTERM: if (f == MOUNT_SUCCESS) { if (m->from_proc_self_mountinfo) { /* Still a mount point? If so, let's * try again. Most likely there were * multiple mount points stacked on * top of each other. Note that due to * the io event priority logic we can * be sure the new mountinfo is loaded * before we process the SIGCHLD for * the mount command. */ if (m->n_retry_umount < RETRY_UMOUNT_MAX) { log_unit_debug(u, "Mount still present, trying again."); m->n_retry_umount++; mount_enter_unmounting(m); } else { log_unit_debug(u, "Mount still present after %u attempts to unmount, giving up.", m->n_retry_umount); mount_enter_mounted(m, f); } } else mount_enter_dead(m, f); } else if (m->from_proc_self_mountinfo) mount_enter_mounted(m, f); else mount_enter_dead(m, f); break; default: assert_not_reached("Uh, control process died at wrong time."); } /* Notify clients about changed exit status */ unit_add_to_dbus_queue(u); } static int mount_dispatch_timer(sd_event_source *source, usec_t usec, void *userdata) { Mount *m = MOUNT(userdata); assert(m); assert(m->timer_event_source == source); switch (m->state) { case MOUNT_MOUNTING: case MOUNT_MOUNTING_DONE: log_unit_warning(UNIT(m), "Mounting timed out. Stopping."); mount_enter_signal(m, MOUNT_MOUNTING_SIGTERM, MOUNT_FAILURE_TIMEOUT); break; case MOUNT_REMOUNTING: log_unit_warning(UNIT(m), "Remounting timed out. Stopping."); m->reload_result = MOUNT_FAILURE_TIMEOUT; mount_enter_mounted(m, MOUNT_SUCCESS); break; case MOUNT_UNMOUNTING: log_unit_warning(UNIT(m), "Unmounting timed out. Stopping."); mount_enter_signal(m, MOUNT_UNMOUNTING_SIGTERM, MOUNT_FAILURE_TIMEOUT); break; case MOUNT_MOUNTING_SIGTERM: if (m->kill_context.send_sigkill) { log_unit_warning(UNIT(m), "Mounting timed out. Killing."); mount_enter_signal(m, MOUNT_MOUNTING_SIGKILL, MOUNT_FAILURE_TIMEOUT); } else { log_unit_warning(UNIT(m), "Mounting timed out. Skipping SIGKILL. Ignoring."); if (m->from_proc_self_mountinfo) mount_enter_mounted(m, MOUNT_FAILURE_TIMEOUT); else mount_enter_dead(m, MOUNT_FAILURE_TIMEOUT); } break; case MOUNT_REMOUNTING_SIGTERM: if (m->kill_context.send_sigkill) { log_unit_warning(UNIT(m), "Remounting timed out. Killing."); mount_enter_signal(m, MOUNT_REMOUNTING_SIGKILL, MOUNT_FAILURE_TIMEOUT); } else { log_unit_warning(UNIT(m), "Remounting timed out. Skipping SIGKILL. Ignoring."); if (m->from_proc_self_mountinfo) mount_enter_mounted(m, MOUNT_FAILURE_TIMEOUT); else mount_enter_dead(m, MOUNT_FAILURE_TIMEOUT); } break; case MOUNT_UNMOUNTING_SIGTERM: if (m->kill_context.send_sigkill) { log_unit_warning(UNIT(m), "Unmounting timed out. Killing."); mount_enter_signal(m, MOUNT_UNMOUNTING_SIGKILL, MOUNT_FAILURE_TIMEOUT); } else { log_unit_warning(UNIT(m), "Unmounting timed out. Skipping SIGKILL. Ignoring."); if (m->from_proc_self_mountinfo) mount_enter_mounted(m, MOUNT_FAILURE_TIMEOUT); else mount_enter_dead(m, MOUNT_FAILURE_TIMEOUT); } break; case MOUNT_MOUNTING_SIGKILL: case MOUNT_REMOUNTING_SIGKILL: case MOUNT_UNMOUNTING_SIGKILL: log_unit_warning(UNIT(m),"Mount process still around after SIGKILL. Ignoring."); if (m->from_proc_self_mountinfo) mount_enter_mounted(m, MOUNT_FAILURE_TIMEOUT); else mount_enter_dead(m, MOUNT_FAILURE_TIMEOUT); break; default: assert_not_reached("Timeout at wrong time."); } return 0; } static int mount_setup_unit( Manager *m, const char *what, const char *where, const char *options, const char *fstype, bool set_flags) { _cleanup_free_ char *e = NULL, *w = NULL, *o = NULL, *f = NULL; bool load_extras = false; MountParameters *p; bool delete, changed = false; Unit *u; int r; assert(m); assert(what); assert(where); assert(options); assert(fstype); /* Ignore API mount points. They should never be referenced in * dependencies ever. */ if (mount_point_is_api(where) || mount_point_ignore(where)) return 0; if (streq(fstype, "autofs")) return 0; /* probably some kind of swap, ignore */ if (!is_path(where)) return 0; r = unit_name_from_path(where, ".mount", &e); if (r < 0) return r; u = manager_get_unit(m, e); if (!u) { delete = true; u = unit_new(m, sizeof(Mount)); if (!u) return log_oom(); r = unit_add_name(u, e); if (r < 0) goto fail; MOUNT(u)->where = strdup(where); if (!MOUNT(u)->where) { r = -ENOMEM; goto fail; } u->source_path = strdup("/proc/self/mountinfo"); if (!u->source_path) { r = -ENOMEM; goto fail; } if (MANAGER_IS_SYSTEM(m)) { const char* target; target = mount_needs_network(options, fstype) ? SPECIAL_REMOTE_FS_TARGET : SPECIAL_LOCAL_FS_TARGET; r = unit_add_dependency_by_name(u, UNIT_BEFORE, target, NULL, true); if (r < 0) goto fail; if (should_umount(MOUNT(u))) { r = unit_add_dependency_by_name(u, UNIT_CONFLICTS, SPECIAL_UMOUNT_TARGET, NULL, true); if (r < 0) goto fail; } } unit_add_to_load_queue(u); changed = true; } else { delete = false; if (!MOUNT(u)->where) { MOUNT(u)->where = strdup(where); if (!MOUNT(u)->where) { r = -ENOMEM; goto fail; } } if (MANAGER_IS_SYSTEM(m) && mount_needs_network(options, fstype)) { /* _netdev option may have shown up late, or on a * remount. Add remote-fs dependencies, even though * local-fs ones may already be there. */ unit_add_dependency_by_name(u, UNIT_BEFORE, SPECIAL_REMOTE_FS_TARGET, NULL, true); load_extras = true; } if (u->load_state == UNIT_NOT_FOUND) { u->load_state = UNIT_LOADED; u->load_error = 0; /* Load in the extras later on, after we * finished initialization of the unit */ load_extras = true; changed = true; } } w = strdup(what); o = strdup(options); f = strdup(fstype); if (!w || !o || !f) { r = -ENOMEM; goto fail; } p = &MOUNT(u)->parameters_proc_self_mountinfo; changed = changed || !streq_ptr(p->options, options) || !streq_ptr(p->what, what) || !streq_ptr(p->fstype, fstype); if (set_flags) { MOUNT(u)->is_mounted = true; MOUNT(u)->just_mounted = !MOUNT(u)->from_proc_self_mountinfo; MOUNT(u)->just_changed = changed; } MOUNT(u)->from_proc_self_mountinfo = true; free(p->what); p->what = w; w = NULL; free(p->options); p->options = o; o = NULL; free(p->fstype); p->fstype = f; f = NULL; if (load_extras) { r = mount_add_extras(MOUNT(u)); if (r < 0) goto fail; } if (changed) unit_add_to_dbus_queue(u); return 0; fail: log_warning_errno(r, "Failed to set up mount unit: %m"); if (delete && u) unit_free(u); return r; } static int mount_load_proc_self_mountinfo(Manager *m, bool set_flags) { _cleanup_(mnt_free_tablep) struct libmnt_table *t = NULL; _cleanup_(mnt_free_iterp) struct libmnt_iter *i = NULL; int r = 0; assert(m); t = mnt_new_table(); if (!t) return log_oom(); i = mnt_new_iter(MNT_ITER_FORWARD); if (!i) return log_oom(); r = mnt_table_parse_mtab(t, NULL); if (r < 0) return log_error_errno(r, "Failed to parse /proc/self/mountinfo: %m"); r = 0; for (;;) { const char *device, *path, *options, *fstype; _cleanup_free_ char *d = NULL, *p = NULL; struct libmnt_fs *fs; int k; k = mnt_table_next_fs(t, i, &fs); if (k == 1) break; if (k < 0) return log_error_errno(k, "Failed to get next entry from /proc/self/mountinfo: %m"); device = mnt_fs_get_source(fs); path = mnt_fs_get_target(fs); options = mnt_fs_get_options(fs); fstype = mnt_fs_get_fstype(fs); if (!device || !path) continue; if (cunescape(device, UNESCAPE_RELAX, &d) < 0) return log_oom(); if (cunescape(path, UNESCAPE_RELAX, &p) < 0) return log_oom(); (void) device_found_node(m, d, true, DEVICE_FOUND_MOUNT, set_flags); k = mount_setup_unit(m, d, p, options, fstype, set_flags); if (r == 0 && k < 0) r = k; } return r; } static void mount_shutdown(Manager *m) { assert(m); m->mount_event_source = sd_event_source_unref(m->mount_event_source); mnt_unref_monitor(m->mount_monitor); m->mount_monitor = NULL; } static int mount_get_timeout(Unit *u, usec_t *timeout) { Mount *m = MOUNT(u); usec_t t; int r; if (!m->timer_event_source) return 0; r = sd_event_source_get_time(m->timer_event_source, &t); if (r < 0) return r; if (t == USEC_INFINITY) return 0; *timeout = t; return 1; } static void mount_enumerate(Manager *m) { int r; assert(m); mnt_init_debug(0); if (!m->mount_monitor) { int fd; m->mount_monitor = mnt_new_monitor(); if (!m->mount_monitor) { log_oom(); goto fail; } r = mnt_monitor_enable_kernel(m->mount_monitor, 1); if (r < 0) { log_error_errno(r, "Failed to enable watching of kernel mount events: %m"); goto fail; } r = mnt_monitor_enable_userspace(m->mount_monitor, 1, NULL); if (r < 0) { log_error_errno(r, "Failed to enable watching of userspace mount events: %m"); goto fail; } /* mnt_unref_monitor() will close the fd */ fd = r = mnt_monitor_get_fd(m->mount_monitor); if (r < 0) { log_error_errno(r, "Failed to acquire watch file descriptor: %m"); goto fail; } r = sd_event_add_io(m->event, &m->mount_event_source, fd, EPOLLIN, mount_dispatch_io, m); if (r < 0) { log_error_errno(r, "Failed to watch mount file descriptor: %m"); goto fail; } r = sd_event_source_set_priority(m->mount_event_source, -10); if (r < 0) { log_error_errno(r, "Failed to adjust mount watch priority: %m"); goto fail; } (void) sd_event_source_set_description(m->mount_event_source, "mount-monitor-dispatch"); } r = mount_load_proc_self_mountinfo(m, false); if (r < 0) goto fail; return; fail: mount_shutdown(m); } static int mount_dispatch_io(sd_event_source *source, int fd, uint32_t revents, void *userdata) { _cleanup_set_free_ Set *around = NULL, *gone = NULL; Manager *m = userdata; const char *what; Iterator i; Unit *u; int r; assert(m); assert(revents & EPOLLIN); if (fd == mnt_monitor_get_fd(m->mount_monitor)) { bool rescan = false; /* Drain all events and verify that the event is valid. * * Note that libmount also monitors /run/mount mkdir if the * directory does not exist yet. The mkdir may generate event * which is irrelevant for us. * * error: r < 0; valid: r == 0, false positive: rc == 1 */ do { r = mnt_monitor_next_change(m->mount_monitor, NULL, NULL); if (r == 0) rescan = true; else if (r < 0) return log_error_errno(r, "Failed to drain libmount events"); } while (r == 0); log_debug("libmount event [rescan: %s]", yes_no(rescan)); if (!rescan) return 0; } r = mount_load_proc_self_mountinfo(m, true); if (r < 0) { /* Reset flags, just in case, for later calls */ LIST_FOREACH(units_by_type, u, m->units_by_type[UNIT_MOUNT]) { Mount *mount = MOUNT(u); mount->is_mounted = mount->just_mounted = mount->just_changed = false; } return 0; } manager_dispatch_load_queue(m); LIST_FOREACH(units_by_type, u, m->units_by_type[UNIT_MOUNT]) { Mount *mount = MOUNT(u); if (!mount->is_mounted) { /* A mount point is not around right now. It * might be gone, or might never have * existed. */ if (mount->from_proc_self_mountinfo && mount->parameters_proc_self_mountinfo.what) { /* Remember that this device might just have disappeared */ if (set_ensure_allocated(&gone, &string_hash_ops) < 0 || set_put(gone, mount->parameters_proc_self_mountinfo.what) < 0) log_oom(); /* we don't care too much about OOM here... */ } mount->from_proc_self_mountinfo = false; switch (mount->state) { case MOUNT_MOUNTED: /* This has just been unmounted by * somebody else, follow the state * change. */ mount->result = MOUNT_SUCCESS; /* make sure we forget any earlier umount failures */ mount_enter_dead(mount, MOUNT_SUCCESS); break; default: break; } } else if (mount->just_mounted || mount->just_changed) { /* A mount point was added or changed */ switch (mount->state) { case MOUNT_DEAD: case MOUNT_FAILED: /* This has just been mounted by * somebody else, follow the state * change. */ mount_enter_mounted(mount, MOUNT_SUCCESS); break; case MOUNT_MOUNTING: mount_set_state(mount, MOUNT_MOUNTING_DONE); break; default: /* Nothing really changed, but let's * issue an notification call * nonetheless, in case somebody is * waiting for this. (e.g. file system * ro/rw remounts.) */ mount_set_state(mount, mount->state); break; } } if (mount->is_mounted && mount->from_proc_self_mountinfo && mount->parameters_proc_self_mountinfo.what) { if (set_ensure_allocated(&around, &string_hash_ops) < 0 || set_put(around, mount->parameters_proc_self_mountinfo.what) < 0) log_oom(); } /* Reset the flags for later calls */ mount->is_mounted = mount->just_mounted = mount->just_changed = false; } SET_FOREACH(what, gone, i) { if (set_contains(around, what)) continue; /* Let the device units know that the device is no longer mounted */ (void) device_found_node(m, what, false, DEVICE_FOUND_MOUNT, true); } return 0; } static void mount_reset_failed(Unit *u) { Mount *m = MOUNT(u); assert(m); if (m->state == MOUNT_FAILED) mount_set_state(m, MOUNT_DEAD); m->result = MOUNT_SUCCESS; m->reload_result = MOUNT_SUCCESS; } static int mount_kill(Unit *u, KillWho who, int signo, sd_bus_error *error) { return unit_kill_common(u, who, signo, -1, MOUNT(u)->control_pid, error); } static int mount_control_pid(Unit *u) { Mount *m = MOUNT(u); assert(m); return m->control_pid; } static const char* const mount_exec_command_table[_MOUNT_EXEC_COMMAND_MAX] = { [MOUNT_EXEC_MOUNT] = "ExecMount", [MOUNT_EXEC_UNMOUNT] = "ExecUnmount", [MOUNT_EXEC_REMOUNT] = "ExecRemount", }; DEFINE_STRING_TABLE_LOOKUP(mount_exec_command, MountExecCommand); static const char* const mount_result_table[_MOUNT_RESULT_MAX] = { [MOUNT_SUCCESS] = "success", [MOUNT_FAILURE_RESOURCES] = "resources", [MOUNT_FAILURE_TIMEOUT] = "timeout", [MOUNT_FAILURE_EXIT_CODE] = "exit-code", [MOUNT_FAILURE_SIGNAL] = "signal", [MOUNT_FAILURE_CORE_DUMP] = "core-dump", [MOUNT_FAILURE_START_LIMIT_HIT] = "start-limit-hit", }; DEFINE_STRING_TABLE_LOOKUP(mount_result, MountResult); const UnitVTable mount_vtable = { .object_size = sizeof(Mount), .exec_context_offset = offsetof(Mount, exec_context), .cgroup_context_offset = offsetof(Mount, cgroup_context), .kill_context_offset = offsetof(Mount, kill_context), .exec_runtime_offset = offsetof(Mount, exec_runtime), .dynamic_creds_offset = offsetof(Mount, dynamic_creds), .sections = "Unit\0" "Mount\0" "Install\0", .private_section = "Mount", .init = mount_init, .load = mount_load, .done = mount_done, .coldplug = mount_coldplug, .dump = mount_dump, .start = mount_start, .stop = mount_stop, .reload = mount_reload, .kill = mount_kill, .serialize = mount_serialize, .deserialize_item = mount_deserialize_item, .active_state = mount_active_state, .sub_state_to_string = mount_sub_state_to_string, .check_gc = mount_check_gc, .sigchld_event = mount_sigchld_event, .reset_failed = mount_reset_failed, .control_pid = mount_control_pid, .bus_vtable = bus_mount_vtable, .bus_set_property = bus_mount_set_property, .bus_commit_properties = bus_mount_commit_properties, .get_timeout = mount_get_timeout, .can_transient = true, .enumerate = mount_enumerate, .shutdown = mount_shutdown, .status_message_formats = { .starting_stopping = { [0] = "Mounting %s...", [1] = "Unmounting %s...", }, .finished_start_job = { [JOB_DONE] = "Mounted %s.", [JOB_FAILED] = "Failed to mount %s.", [JOB_TIMEOUT] = "Timed out mounting %s.", }, .finished_stop_job = { [JOB_DONE] = "Unmounted %s.", [JOB_FAILED] = "Failed unmounting %s.", [JOB_TIMEOUT] = "Timed out unmounting %s.", }, }, };