/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/ /*** This file is part of systemd. Copyright 2013 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 <http://www.gnu.org/licenses/>. ***/ #include <errno.h> #include <unistd.h> #include "alloc-util.h" #include "dbus-scope.h" #include "load-dropin.h" #include "log.h" #include "scope.h" #include "special.h" #include "string-table.h" #include "string-util.h" #include "strv.h" #include "unit-name.h" #include "unit.h" static const UnitActiveState state_translation_table[_SCOPE_STATE_MAX] = { [SCOPE_DEAD] = UNIT_INACTIVE, [SCOPE_RUNNING] = UNIT_ACTIVE, [SCOPE_ABANDONED] = UNIT_ACTIVE, [SCOPE_STOP_SIGTERM] = UNIT_DEACTIVATING, [SCOPE_STOP_SIGKILL] = UNIT_DEACTIVATING, [SCOPE_FAILED] = UNIT_FAILED }; static int scope_dispatch_timer(sd_event_source *source, usec_t usec, void *userdata); static void scope_init(Unit *u) { Scope *s = SCOPE(u); assert(u); assert(u->load_state == UNIT_STUB); s->timeout_stop_usec = u->manager->default_timeout_stop_usec; UNIT(s)->ignore_on_isolate = true; UNIT(s)->ignore_on_snapshot = true; } static void scope_done(Unit *u) { Scope *s = SCOPE(u); assert(u); free(s->controller); s->timer_event_source = sd_event_source_unref(s->timer_event_source); } static int scope_arm_timer(Scope *s) { int r; assert(s); if (s->timeout_stop_usec <= 0) { s->timer_event_source = sd_event_source_unref(s->timer_event_source); return 0; } if (s->timer_event_source) { r = sd_event_source_set_time(s->timer_event_source, now(CLOCK_MONOTONIC) + s->timeout_stop_usec); if (r < 0) return r; return sd_event_source_set_enabled(s->timer_event_source, SD_EVENT_ONESHOT); } r = sd_event_add_time( UNIT(s)->manager->event, &s->timer_event_source, CLOCK_MONOTONIC, now(CLOCK_MONOTONIC) + s->timeout_stop_usec, 0, scope_dispatch_timer, s); if (r < 0) return r; (void) sd_event_source_set_description(s->timer_event_source, "scope-timer"); return 0; } static void scope_set_state(Scope *s, ScopeState state) { ScopeState old_state; assert(s); old_state = s->state; s->state = state; if (!IN_SET(state, SCOPE_STOP_SIGTERM, SCOPE_STOP_SIGKILL)) s->timer_event_source = sd_event_source_unref(s->timer_event_source); if (IN_SET(state, SCOPE_DEAD, SCOPE_FAILED)) unit_unwatch_all_pids(UNIT(s)); if (state != old_state) log_debug("%s changed %s -> %s", UNIT(s)->id, scope_state_to_string(old_state), scope_state_to_string(state)); unit_notify(UNIT(s), state_translation_table[old_state], state_translation_table[state], true); } static int scope_add_default_dependencies(Scope *s) { int r; assert(s); /* Make sure scopes are unloaded on shutdown */ r = unit_add_two_dependencies_by_name( UNIT(s), UNIT_BEFORE, UNIT_CONFLICTS, SPECIAL_SHUTDOWN_TARGET, NULL, true); if (r < 0) return r; return 0; } static int scope_verify(Scope *s) { assert(s); if (UNIT(s)->load_state != UNIT_LOADED) return 0; if (set_isempty(UNIT(s)->pids) && !manager_is_reloading_or_reexecuting(UNIT(s)->manager) && !unit_has_name(UNIT(s), SPECIAL_INIT_SCOPE)) { log_unit_error(UNIT(s), "Scope has no PIDs. Refusing."); return -EINVAL; } return 0; } static int scope_load(Unit *u) { Scope *s = SCOPE(u); int r; assert(s); assert(u->load_state == UNIT_STUB); if (!u->transient && !manager_is_reloading_or_reexecuting(u->manager)) return -ENOENT; u->load_state = UNIT_LOADED; r = unit_load_dropin(u); if (r < 0) return r; r = unit_patch_contexts(u); if (r < 0) return r; r = unit_set_default_slice(u); if (r < 0) return r; if (u->default_dependencies) { r = scope_add_default_dependencies(s); if (r < 0) return r; } return scope_verify(s); } static int scope_coldplug(Unit *u) { Scope *s = SCOPE(u); int r; assert(s); assert(s->state == SCOPE_DEAD); if (s->deserialized_state != s->state) { if (IN_SET(s->deserialized_state, SCOPE_STOP_SIGKILL, SCOPE_STOP_SIGTERM)) { r = scope_arm_timer(s); if (r < 0) return r; } if (!IN_SET(s->deserialized_state, SCOPE_DEAD, SCOPE_FAILED)) unit_watch_all_pids(UNIT(s)); scope_set_state(s, s->deserialized_state); } return 0; } static void scope_dump(Unit *u, FILE *f, const char *prefix) { Scope *s = SCOPE(u); assert(s); assert(f); fprintf(f, "%sScope State: %s\n" "%sResult: %s\n", prefix, scope_state_to_string(s->state), prefix, scope_result_to_string(s->result)); cgroup_context_dump(&s->cgroup_context, f, prefix); kill_context_dump(&s->kill_context, f, prefix); } static void scope_enter_dead(Scope *s, ScopeResult f) { assert(s); if (f != SCOPE_SUCCESS) s->result = f; scope_set_state(s, s->result != SCOPE_SUCCESS ? SCOPE_FAILED : SCOPE_DEAD); } static void scope_enter_signal(Scope *s, ScopeState state, ScopeResult f) { bool skip_signal = false; int r; assert(s); if (f != SCOPE_SUCCESS) s->result = f; unit_watch_all_pids(UNIT(s)); /* If we have a controller set let's ask the controller nicely * to terminate the scope, instead of us going directly into * SIGTERM beserk mode */ if (state == SCOPE_STOP_SIGTERM) skip_signal = bus_scope_send_request_stop(s) > 0; if (!skip_signal) { r = unit_kill_context( UNIT(s), &s->kill_context, state != SCOPE_STOP_SIGTERM ? KILL_KILL : KILL_TERMINATE, -1, -1, false); if (r < 0) goto fail; } else r = 1; if (r > 0) { r = scope_arm_timer(s); if (r < 0) goto fail; scope_set_state(s, state); } else if (state == SCOPE_STOP_SIGTERM) scope_enter_signal(s, SCOPE_STOP_SIGKILL, SCOPE_SUCCESS); else scope_enter_dead(s, SCOPE_SUCCESS); return; fail: log_unit_warning_errno(UNIT(s), r, "Failed to kill processes: %m"); scope_enter_dead(s, SCOPE_FAILURE_RESOURCES); } static int scope_start(Unit *u) { Scope *s = SCOPE(u); int r; assert(s); if (unit_has_name(u, SPECIAL_INIT_SCOPE)) return -EPERM; if (s->state == SCOPE_FAILED) return -EPERM; /* We can't fulfill this right now, please try again later */ if (s->state == SCOPE_STOP_SIGTERM || s->state == SCOPE_STOP_SIGKILL) return -EAGAIN; assert(s->state == SCOPE_DEAD); if (!u->transient && !manager_is_reloading_or_reexecuting(u->manager)) return -ENOENT; (void) unit_realize_cgroup(u); (void) unit_reset_cpu_usage(u); r = unit_attach_pids_to_cgroup(u); if (r < 0) { log_unit_warning_errno(UNIT(s), r, "Failed to add PIDs to scope's control group: %m"); scope_enter_dead(s, SCOPE_FAILURE_RESOURCES); return r; } s->result = SCOPE_SUCCESS; scope_set_state(s, SCOPE_RUNNING); return 1; } static int scope_stop(Unit *u) { Scope *s = SCOPE(u); assert(s); if (s->state == SCOPE_STOP_SIGTERM || s->state == SCOPE_STOP_SIGKILL) return 0; assert(s->state == SCOPE_RUNNING || s->state == SCOPE_ABANDONED); scope_enter_signal(s, SCOPE_STOP_SIGTERM, SCOPE_SUCCESS); return 1; } static void scope_reset_failed(Unit *u) { Scope *s = SCOPE(u); assert(s); if (s->state == SCOPE_FAILED) scope_set_state(s, SCOPE_DEAD); s->result = SCOPE_SUCCESS; } static int scope_kill(Unit *u, KillWho who, int signo, sd_bus_error *error) { return unit_kill_common(u, who, signo, -1, -1, error); } static int scope_get_timeout(Unit *u, uint64_t *timeout) { Scope *s = SCOPE(u); int r; if (!s->timer_event_source) return 0; r = sd_event_source_get_time(s->timer_event_source, timeout); if (r < 0) return r; return 1; } static int scope_serialize(Unit *u, FILE *f, FDSet *fds) { Scope *s = SCOPE(u); assert(s); assert(f); assert(fds); unit_serialize_item(u, f, "state", scope_state_to_string(s->state)); return 0; } static int scope_deserialize_item(Unit *u, const char *key, const char *value, FDSet *fds) { Scope *s = SCOPE(u); assert(u); assert(key); assert(value); assert(fds); if (streq(key, "state")) { ScopeState state; state = scope_state_from_string(value); if (state < 0) log_unit_debug(u, "Failed to parse state value: %s", value); else s->deserialized_state = state; } else log_unit_debug(u, "Unknown serialization key: %s", key); return 0; } static bool scope_check_gc(Unit *u) { assert(u); /* Never clean up scopes that still have a process around, * even if the scope is formally dead. */ if (u->cgroup_path) { int r; r = cg_is_empty_recursive(SYSTEMD_CGROUP_CONTROLLER, u->cgroup_path); if (r <= 0) return true; } return false; } static void scope_notify_cgroup_empty_event(Unit *u) { Scope *s = SCOPE(u); assert(u); log_unit_debug(u, "cgroup is empty"); if (IN_SET(s->state, SCOPE_RUNNING, SCOPE_ABANDONED, SCOPE_STOP_SIGTERM, SCOPE_STOP_SIGKILL)) scope_enter_dead(s, SCOPE_SUCCESS); } static void scope_sigchld_event(Unit *u, pid_t pid, int code, int status) { /* If we get a SIGCHLD event for one of the processes we were interested in, then we look for others to watch, under the assumption that we'll sooner or later get a SIGCHLD for them, as the original process we watched was probably the parent of them, and they are hence now our children. */ unit_tidy_watch_pids(u, 0, 0); unit_watch_all_pids(u); /* If the PID set is empty now, then let's finish this off */ if (set_isempty(u->pids)) scope_notify_cgroup_empty_event(u); } static int scope_dispatch_timer(sd_event_source *source, usec_t usec, void *userdata) { Scope *s = SCOPE(userdata); assert(s); assert(s->timer_event_source == source); switch (s->state) { case SCOPE_STOP_SIGTERM: if (s->kill_context.send_sigkill) { log_unit_warning(UNIT(s), "Stopping timed out. Killing."); scope_enter_signal(s, SCOPE_STOP_SIGKILL, SCOPE_FAILURE_TIMEOUT); } else { log_unit_warning(UNIT(s), "Stopping timed out. Skipping SIGKILL."); scope_enter_dead(s, SCOPE_FAILURE_TIMEOUT); } break; case SCOPE_STOP_SIGKILL: log_unit_warning(UNIT(s), "Still around after SIGKILL. Ignoring."); scope_enter_dead(s, SCOPE_FAILURE_TIMEOUT); break; default: assert_not_reached("Timeout at wrong time."); } return 0; } int scope_abandon(Scope *s) { assert(s); if (unit_has_name(UNIT(s), SPECIAL_INIT_SCOPE)) return -EPERM; if (!IN_SET(s->state, SCOPE_RUNNING, SCOPE_ABANDONED)) return -ESTALE; s->controller = mfree(s->controller); /* The client is no longer watching the remaining processes, * so let's step in here, under the assumption that the * remaining processes will be sooner or later reassigned to * us as parent. */ unit_tidy_watch_pids(UNIT(s), 0, 0); unit_watch_all_pids(UNIT(s)); /* If the PID set is empty now, then let's finish this off */ if (set_isempty(UNIT(s)->pids)) scope_notify_cgroup_empty_event(UNIT(s)); else scope_set_state(s, SCOPE_ABANDONED); return 0; } _pure_ static UnitActiveState scope_active_state(Unit *u) { assert(u); return state_translation_table[SCOPE(u)->state]; } _pure_ static const char *scope_sub_state_to_string(Unit *u) { assert(u); return scope_state_to_string(SCOPE(u)->state); } static void scope_enumerate(Manager *m) { Unit *u; int r; assert(m); /* Let's unconditionally add the "init.scope" special unit * that encapsulates PID 1. Note that PID 1 already is in the * cgroup for this, we hence just need to allocate the object * for it and that's it. */ u = manager_get_unit(m, SPECIAL_INIT_SCOPE); if (!u) { u = unit_new(m, sizeof(Scope)); if (!u) { log_oom(); return; } r = unit_add_name(u, SPECIAL_INIT_SCOPE); if (r < 0) { unit_free(u); log_error_errno(r, "Failed to add init.scope name"); return; } } u->transient = true; u->default_dependencies = false; u->no_gc = true; u->ignore_on_isolate = true; u->refuse_manual_start = true; u->refuse_manual_stop = true; SCOPE(u)->deserialized_state = SCOPE_RUNNING; SCOPE(u)->kill_context.kill_signal = SIGRTMIN+14; /* Prettify things, if we can. */ if (!u->description) u->description = strdup("System and Service Manager"); if (!u->documentation) (void) strv_extend(&u->documentation, "man:systemd(1)"); unit_add_to_load_queue(u); unit_add_to_dbus_queue(u); } static const char* const scope_result_table[_SCOPE_RESULT_MAX] = { [SCOPE_SUCCESS] = "success", [SCOPE_FAILURE_RESOURCES] = "resources", [SCOPE_FAILURE_TIMEOUT] = "timeout", }; DEFINE_STRING_TABLE_LOOKUP(scope_result, ScopeResult); const UnitVTable scope_vtable = { .object_size = sizeof(Scope), .cgroup_context_offset = offsetof(Scope, cgroup_context), .kill_context_offset = offsetof(Scope, kill_context), .sections = "Unit\0" "Scope\0" "Install\0", .private_section = "Scope", .no_alias = true, .no_instances = true, .init = scope_init, .load = scope_load, .done = scope_done, .coldplug = scope_coldplug, .dump = scope_dump, .start = scope_start, .stop = scope_stop, .kill = scope_kill, .get_timeout = scope_get_timeout, .serialize = scope_serialize, .deserialize_item = scope_deserialize_item, .active_state = scope_active_state, .sub_state_to_string = scope_sub_state_to_string, .check_gc = scope_check_gc, .sigchld_event = scope_sigchld_event, .reset_failed = scope_reset_failed, .notify_cgroup_empty = scope_notify_cgroup_empty_event, .bus_vtable = bus_scope_vtable, .bus_set_property = bus_scope_set_property, .bus_commit_properties = bus_scope_commit_properties, .can_transient = true, .enumerate = scope_enumerate, };