move libsystemd_core.la sources into core/

1 files changed, 1415 insertions, 0 deletions

diff --git a/src/core/swap.c b/src/core/swap.c
new file mode 100644
index 0000000000..9c72732b94
--- /dev/null
+++ b/src/core/swap.c
@@ -0,0 +1,1415 @@
+/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
+
+/***
+  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 General Public License as published by
+  the Free Software Foundation; either version 2 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
+  General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include <errno.h>
+#include <limits.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <sys/epoll.h>
+#include <sys/stat.h>
+#include <sys/swap.h>
+#include <libudev.h>
+
+#include "unit.h"
+#include "swap.h"
+#include "load-fragment.h"
+#include "load-dropin.h"
+#include "unit-name.h"
+#include "dbus-swap.h"
+#include "special.h"
+#include "bus-errors.h"
+#include "exit-status.h"
+#include "def.h"
+
+static const UnitActiveState state_translation_table[_SWAP_STATE_MAX] = {
+        [SWAP_DEAD] = UNIT_INACTIVE,
+        [SWAP_ACTIVATING] = UNIT_ACTIVATING,
+        [SWAP_ACTIVE] = UNIT_ACTIVE,
+        [SWAP_DEACTIVATING] = UNIT_DEACTIVATING,
+        [SWAP_ACTIVATING_SIGTERM] = UNIT_DEACTIVATING,
+        [SWAP_ACTIVATING_SIGKILL] = UNIT_DEACTIVATING,
+        [SWAP_DEACTIVATING_SIGTERM] = UNIT_DEACTIVATING,
+        [SWAP_DEACTIVATING_SIGKILL] = UNIT_DEACTIVATING,
+        [SWAP_FAILED] = UNIT_FAILED
+};
+
+static void swap_unset_proc_swaps(Swap *s) {
+        Swap *first;
+
+        assert(s);
+
+        if (!s->parameters_proc_swaps.what)
+                return;
+
+        /* Remove this unit from the chain of swaps which share the
+         * same kernel swap device. */
+
+        first = hashmap_get(UNIT(s)->manager->swaps_by_proc_swaps, s->parameters_proc_swaps.what);
+        LIST_REMOVE(Swap, same_proc_swaps, first, s);
+
+        if (first)
+                hashmap_remove_and_replace(UNIT(s)->manager->swaps_by_proc_swaps, s->parameters_proc_swaps.what, first->parameters_proc_swaps.what, first);
+        else
+                hashmap_remove(UNIT(s)->manager->swaps_by_proc_swaps, s->parameters_proc_swaps.what);
+
+        free(s->parameters_proc_swaps.what);
+        s->parameters_proc_swaps.what = NULL;
+}
+
+static void swap_init(Unit *u) {
+        Swap *s = SWAP(u);
+
+        assert(s);
+        assert(UNIT(s)->load_state == UNIT_STUB);
+
+        s->timeout_usec = DEFAULT_TIMEOUT_USEC;
+
+        exec_context_init(&s->exec_context);
+        s->exec_context.std_output = u->manager->default_std_output;
+        s->exec_context.std_error = u->manager->default_std_error;
+
+        s->parameters_etc_fstab.priority = s->parameters_proc_swaps.priority = s->parameters_fragment.priority = -1;
+
+        s->timer_watch.type = WATCH_INVALID;
+
+        s->control_command_id = _SWAP_EXEC_COMMAND_INVALID;
+
+        UNIT(s)->ignore_on_isolate = true;
+}
+
+static void swap_unwatch_control_pid(Swap *s) {
+        assert(s);
+
+        if (s->control_pid <= 0)
+                return;
+
+        unit_unwatch_pid(UNIT(s), s->control_pid);
+        s->control_pid = 0;
+}
+
+static void swap_done(Unit *u) {
+        Swap *s = SWAP(u);
+
+        assert(s);
+
+        swap_unset_proc_swaps(s);
+
+        free(s->what);
+        s->what = NULL;
+
+        free(s->parameters_etc_fstab.what);
+        free(s->parameters_fragment.what);
+        s->parameters_etc_fstab.what = s->parameters_fragment.what = NULL;
+
+        exec_context_done(&s->exec_context);
+        exec_command_done_array(s->exec_command, _SWAP_EXEC_COMMAND_MAX);
+        s->control_command = NULL;
+
+        swap_unwatch_control_pid(s);
+
+        unit_unwatch_timer(u, &s->timer_watch);
+}
+
+int swap_add_one_mount_link(Swap *s, Mount *m) {
+         int r;
+
+        assert(s);
+        assert(m);
+
+        if (UNIT(s)->load_state != UNIT_LOADED ||
+            UNIT(m)->load_state != UNIT_LOADED)
+                return 0;
+
+        if (is_device_path(s->what))
+                return 0;
+
+        if (!path_startswith(s->what, m->where))
+                return 0;
+
+        if ((r = unit_add_two_dependencies(UNIT(s), UNIT_AFTER, UNIT_REQUIRES, UNIT(m), true)) < 0)
+                return r;
+
+        return 0;
+}
+
+static int swap_add_mount_links(Swap *s) {
+        Unit *other;
+        int r;
+
+        assert(s);
+
+        LIST_FOREACH(units_by_type, other, UNIT(s)->manager->units_by_type[UNIT_MOUNT])
+                if ((r = swap_add_one_mount_link(s, MOUNT(other))) < 0)
+                        return r;
+
+        return 0;
+}
+
+static int swap_add_target_links(Swap *s) {
+        Unit *tu;
+        SwapParameters *p;
+        int r;
+
+        assert(s);
+
+        if (s->from_fragment)
+                p = &s->parameters_fragment;
+        else if (s->from_etc_fstab)
+                p = &s->parameters_etc_fstab;
+        else
+                return 0;
+
+        if ((r = manager_load_unit(UNIT(s)->manager, SPECIAL_SWAP_TARGET, NULL, NULL, &tu)) < 0)
+                return r;
+
+        if (!p->noauto &&
+            !p->nofail &&
+            (p->handle || UNIT(s)->manager->swap_auto) &&
+            s->from_etc_fstab &&
+            UNIT(s)->manager->running_as == MANAGER_SYSTEM)
+                if ((r = unit_add_dependency(tu, UNIT_WANTS, UNIT(s), true)) < 0)
+                        return r;
+
+        return unit_add_dependency(UNIT(s), UNIT_BEFORE, tu, true);
+}
+
+static int swap_add_device_links(Swap *s) {
+        SwapParameters *p;
+
+        assert(s);
+
+        if (!s->what)
+                return 0;
+
+        if (s->from_fragment)
+                p = &s->parameters_fragment;
+        else if (s->from_etc_fstab)
+                p = &s->parameters_etc_fstab;
+        else
+                return 0;
+
+        if (is_device_path(s->what))
+                return unit_add_node_link(UNIT(s), s->what,
+                                          !p->noauto && p->nofail &&
+                                          UNIT(s)->manager->running_as == MANAGER_SYSTEM);
+        else
+                /* File based swap devices need to be ordered after
+                 * remount-rootfs.service, since they might need a
+                 * writable file system. */
+                return unit_add_dependency_by_name(UNIT(s), UNIT_AFTER, SPECIAL_REMOUNT_ROOTFS_SERVICE, NULL, true);
+}
+
+static int swap_add_default_dependencies(Swap *s) {
+        int r;
+
+        assert(s);
+
+        if (UNIT(s)->manager->running_as == MANAGER_SYSTEM) {
+
+                if ((r = unit_add_two_dependencies_by_name(UNIT(s), UNIT_BEFORE, UNIT_CONFLICTS, SPECIAL_UMOUNT_TARGET, NULL, true)) < 0)
+                        return r;
+        }
+
+        return 0;
+}
+
+static int swap_verify(Swap *s) {
+        bool b;
+        char *e;
+
+        if (UNIT(s)->load_state != UNIT_LOADED)
+                  return 0;
+
+        if (!(e = unit_name_from_path(s->what, ".swap")))
+                  return -ENOMEM;
+
+        b = unit_has_name(UNIT(s), e);
+        free(e);
+
+        if (!b) {
+                log_error("%s: Value of \"What\" and unit name do not match, not loading.\n", UNIT(s)->id);
+                return -EINVAL;
+        }
+
+        if (s->exec_context.pam_name && s->exec_context.kill_mode != KILL_CONTROL_GROUP) {
+                log_error("%s has PAM enabled. Kill mode must be set to 'control-group'. Refusing.", UNIT(s)->id);
+                return -EINVAL;
+        }
+
+        return 0;
+}
+
+static int swap_load(Unit *u) {
+        int r;
+        Swap *s = SWAP(u);
+
+        assert(s);
+        assert(u->load_state == UNIT_STUB);
+
+        /* Load a .swap file */
+        if ((r = unit_load_fragment_and_dropin_optional(u)) < 0)
+                return r;
+
+        if (u->load_state == UNIT_LOADED) {
+                if ((r = unit_add_exec_dependencies(u, &s->exec_context)) < 0)
+                        return r;
+
+                if (UNIT(s)->fragment_path)
+                        s->from_fragment = true;
+
+                if (!s->what) {
+                        if (s->parameters_fragment.what)
+                                s->what = strdup(s->parameters_fragment.what);
+                        else if (s->parameters_etc_fstab.what)
+                                s->what = strdup(s->parameters_etc_fstab.what);
+                        else if (s->parameters_proc_swaps.what)
+                                s->what = strdup(s->parameters_proc_swaps.what);
+                        else
+                                s->what = unit_name_to_path(u->id);
+
+                        if (!s->what)
+                                return -ENOMEM;
+                }
+
+                path_kill_slashes(s->what);
+
+                if (!UNIT(s)->description)
+                        if ((r = unit_set_description(u, s->what)) < 0)
+                                return r;
+
+                if ((r = swap_add_device_links(s)) < 0)
+                        return r;
+
+                if ((r = swap_add_mount_links(s)) < 0)
+                        return r;
+
+                if ((r = swap_add_target_links(s)) < 0)
+                        return r;
+
+                if ((r = unit_add_default_cgroups(u)) < 0)
+                        return r;
+
+                if (UNIT(s)->default_dependencies)
+                        if ((r = swap_add_default_dependencies(s)) < 0)
+                                return r;
+        }
+
+        return swap_verify(s);
+}
+
+int swap_add_one(
+                Manager *m,
+                const char *what,
+                const char *what_proc_swaps,
+                int priority,
+                bool noauto,
+                bool nofail,
+                bool handle,
+                bool set_flags) {
+
+        Unit *u = NULL;
+        char *e = NULL, *wp = NULL;
+        bool delete = false;
+        int r;
+        SwapParameters *p;
+
+        assert(m);
+        assert(what);
+
+        e = unit_name_from_path(what, ".swap");
+        if (!e)
+                return -ENOMEM;
+
+        u = manager_get_unit(m, e);
+
+        if (what_proc_swaps &&
+            u &&
+            SWAP(u)->from_proc_swaps &&
+            !path_equal(SWAP(u)->parameters_proc_swaps.what, what_proc_swaps))
+                return -EEXIST;
+
+        if (!u) {
+                delete = true;
+
+                u = unit_new(m, sizeof(Swap));
+                if (!u) {
+                        free(e);
+                        return -ENOMEM;
+                }
+
+                r = unit_add_name(u, e);
+                if (r < 0)
+                        goto fail;
+
+                SWAP(u)->what = strdup(what);
+                if (!SWAP(u)->what) {
+                        r = -ENOMEM;
+                        goto fail;
+                }
+
+                unit_add_to_load_queue(u);
+        } else
+                delete = false;
+
+        if (what_proc_swaps) {
+                Swap *first;
+
+                p = &SWAP(u)->parameters_proc_swaps;
+
+                if (!p->what) {
+                        if (!(wp = strdup(what_proc_swaps))) {
+                                r = -ENOMEM;
+                                goto fail;
+                        }
+
+                        if (!m->swaps_by_proc_swaps)
+                                if (!(m->swaps_by_proc_swaps = hashmap_new(string_hash_func, string_compare_func))) {
+                                        r = -ENOMEM;
+                                        goto fail;
+                                }
+
+                        free(p->what);
+                        p->what = wp;
+
+                        first = hashmap_get(m->swaps_by_proc_swaps, wp);
+                        LIST_PREPEND(Swap, same_proc_swaps, first, SWAP(u));
+
+                        if ((r = hashmap_replace(m->swaps_by_proc_swaps, wp, first)) < 0)
+                                goto fail;
+                }
+
+                if (set_flags) {
+                        SWAP(u)->is_active = true;
+                        SWAP(u)->just_activated = !SWAP(u)->from_proc_swaps;
+                }
+
+                SWAP(u)->from_proc_swaps = true;
+
+        } else {
+                p = &SWAP(u)->parameters_etc_fstab;
+
+                if (!(wp = strdup(what))) {
+                        r = -ENOMEM;
+                        goto fail;
+                }
+
+                free(p->what);
+                p->what = wp;
+
+                SWAP(u)->from_etc_fstab = true;
+        }
+
+        p->priority = priority;
+        p->noauto = noauto;
+        p->nofail = nofail;
+        p->handle = handle;
+
+        unit_add_to_dbus_queue(u);
+
+        free(e);
+
+        return 0;
+
+fail:
+        log_warning("Failed to load swap unit: %s", strerror(-r));
+
+        free(wp);
+        free(e);
+
+        if (delete && u)
+                unit_free(u);
+
+        return r;
+}
+
+static int swap_process_new_swap(Manager *m, const char *device, int prio, bool set_flags) {
+        struct stat st;
+        int r = 0, k;
+
+        assert(m);
+
+        if (stat(device, &st) >= 0 && S_ISBLK(st.st_mode)) {
+                struct udev_device *d;
+                const char *dn;
+                struct udev_list_entry *item = NULL, *first = NULL;
+
+                /* So this is a proper swap device. Create swap units
+                 * for all names this swap device is known under */
+
+                if (!(d = udev_device_new_from_devnum(m->udev, 'b', st.st_rdev)))
+                        return -ENOMEM;
+
+                if ((dn = udev_device_get_devnode(d)))
+                        r = swap_add_one(m, dn, device, prio, false, false, false, set_flags);
+
+                /* Add additional units for all symlinks */
+                first = udev_device_get_devlinks_list_entry(d);
+                udev_list_entry_foreach(item, first) {
+                        const char *p;
+
+                        /* Don't bother with the /dev/block links */
+                        p = udev_list_entry_get_name(item);
+
+                        if (path_startswith(p, "/dev/block/"))
+                                continue;
+
+                        if (stat(p, &st) >= 0)
+                                if ((!S_ISBLK(st.st_mode)) || st.st_rdev != udev_device_get_devnum(d))
+                                        continue;
+
+                        if ((k = swap_add_one(m, p, device, prio, false, false, false, set_flags)) < 0)
+                                r = k;
+                }
+
+                udev_device_unref(d);
+        }
+
+        if ((k = swap_add_one(m, device, device, prio, false, false, false, set_flags)) < 0)
+                r = k;
+
+        return r;
+}
+
+static void swap_set_state(Swap *s, SwapState state) {
+        SwapState old_state;
+
+        assert(s);
+
+        old_state = s->state;
+        s->state = state;
+
+        if (state != SWAP_ACTIVATING &&
+            state != SWAP_ACTIVATING_SIGTERM &&
+            state != SWAP_ACTIVATING_SIGKILL &&
+            state != SWAP_DEACTIVATING &&
+            state != SWAP_DEACTIVATING_SIGTERM &&
+            state != SWAP_DEACTIVATING_SIGKILL) {
+                unit_unwatch_timer(UNIT(s), &s->timer_watch);
+                swap_unwatch_control_pid(s);
+                s->control_command = NULL;
+                s->control_command_id = _SWAP_EXEC_COMMAND_INVALID;
+        }
+
+        if (state != old_state)
+                log_debug("%s changed %s -> %s",
+                          UNIT(s)->id,
+                          swap_state_to_string(old_state),
+                          swap_state_to_string(state));
+
+        unit_notify(UNIT(s), state_translation_table[old_state], state_translation_table[state], true);
+}
+
+static int swap_coldplug(Unit *u) {
+        Swap *s = SWAP(u);
+        SwapState new_state = SWAP_DEAD;
+        int r;
+
+        assert(s);
+        assert(s->state == SWAP_DEAD);
+
+        if (s->deserialized_state != s->state)
+                new_state = s->deserialized_state;
+        else if (s->from_proc_swaps)
+                new_state = SWAP_ACTIVE;
+
+        if (new_state != s->state) {
+
+                if (new_state == SWAP_ACTIVATING ||
+                    new_state == SWAP_ACTIVATING_SIGTERM ||
+                    new_state == SWAP_ACTIVATING_SIGKILL ||
+                    new_state == SWAP_DEACTIVATING ||
+                    new_state == SWAP_DEACTIVATING_SIGTERM ||
+                    new_state == SWAP_DEACTIVATING_SIGKILL) {
+
+                        if (s->control_pid <= 0)
+                                return -EBADMSG;
+
+                        if ((r = unit_watch_pid(UNIT(s), s->control_pid)) < 0)
+                                return r;
+
+                        if ((r = unit_watch_timer(UNIT(s), s->timeout_usec, &s->timer_watch)) < 0)
+                                return r;
+                }
+
+                swap_set_state(s, new_state);
+        }
+
+        return 0;
+}
+
+static void swap_dump(Unit *u, FILE *f, const char *prefix) {
+        Swap *s = SWAP(u);
+        SwapParameters *p;
+
+        assert(s);
+        assert(f);
+
+        if (s->from_proc_swaps)
+                p = &s->parameters_proc_swaps;
+        else if (s->from_fragment)
+                p = &s->parameters_fragment;
+        else
+                p = &s->parameters_etc_fstab;
+
+        fprintf(f,
+                "%sSwap State: %s\n"
+                "%sResult: %s\n"
+                "%sWhat: %s\n"
+                "%sPriority: %i\n"
+                "%sNoAuto: %s\n"
+                "%sNoFail: %s\n"
+                "%sHandle: %s\n"
+                "%sFrom /etc/fstab: %s\n"
+                "%sFrom /proc/swaps: %s\n"
+                "%sFrom fragment: %s\n",
+                prefix, swap_state_to_string(s->state),
+                prefix, swap_result_to_string(s->result),
+                prefix, s->what,
+                prefix, p->priority,
+                prefix, yes_no(p->noauto),
+                prefix, yes_no(p->nofail),
+                prefix, yes_no(p->handle),
+                prefix, yes_no(s->from_etc_fstab),
+                prefix, yes_no(s->from_proc_swaps),
+                prefix, yes_no(s->from_fragment));
+
+        if (s->control_pid > 0)
+                fprintf(f,
+                        "%sControl PID: %lu\n",
+                        prefix, (unsigned long) s->control_pid);
+
+        exec_context_dump(&s->exec_context, f, prefix);
+}
+
+static int swap_spawn(Swap *s, ExecCommand *c, pid_t *_pid) {
+        pid_t pid;
+        int r;
+
+        assert(s);
+        assert(c);
+        assert(_pid);
+
+        if ((r = unit_watch_timer(UNIT(s), s->timeout_usec, &s->timer_watch)) < 0)
+                goto fail;
+
+        if ((r = exec_spawn(c,
+                            NULL,
+                            &s->exec_context,
+                            NULL, 0,
+                            UNIT(s)->manager->environment,
+                            true,
+                            true,
+                            true,
+                            UNIT(s)->manager->confirm_spawn,
+                            UNIT(s)->cgroup_bondings,
+                            UNIT(s)->cgroup_attributes,
+                            &pid)) < 0)
+                goto fail;
+
+        if ((r = unit_watch_pid(UNIT(s), pid)) < 0)
+                /* FIXME: we need to do something here */
+                goto fail;
+
+        *_pid = pid;
+
+        return 0;
+
+fail:
+        unit_unwatch_timer(UNIT(s), &s->timer_watch);
+
+        return r;
+}
+
+static void swap_enter_dead(Swap *s, SwapResult f) {
+        assert(s);
+
+        if (f != SWAP_SUCCESS)
+                s->result = f;
+
+        swap_set_state(s, s->result != SWAP_SUCCESS ? SWAP_FAILED : SWAP_DEAD);
+}
+
+static void swap_enter_active(Swap *s, SwapResult f) {
+        assert(s);
+
+        if (f != SWAP_SUCCESS)
+                s->result = f;
+
+        swap_set_state(s, SWAP_ACTIVE);
+}
+
+static void swap_enter_signal(Swap *s, SwapState state, SwapResult f) {
+        int r;
+        Set *pid_set = NULL;
+        bool wait_for_exit = false;
+
+        assert(s);
+
+        if (f != SWAP_SUCCESS)
+                s->result = f;
+
+        if (s->exec_context.kill_mode != KILL_NONE) {
+                int sig = (state == SWAP_ACTIVATING_SIGTERM ||
+                           state == SWAP_DEACTIVATING_SIGTERM) ? s->exec_context.kill_signal : SIGKILL;
+
+                if (s->control_pid > 0) {
+                        if (kill_and_sigcont(s->control_pid, sig) < 0 && errno != ESRCH)
+
+                                log_warning("Failed to kill control process %li: %m", (long) s->control_pid);
+                        else
+                                wait_for_exit = true;
+                }
+
+                if (s->exec_context.kill_mode == KILL_CONTROL_GROUP) {
+
+                        if (!(pid_set = set_new(trivial_hash_func, trivial_compare_func))) {
+                                r = -ENOMEM;
+                                goto fail;
+                        }
+
+                        /* Exclude the control pid from being killed via the cgroup */
+                        if (s->control_pid > 0)
+                                if ((r = set_put(pid_set, LONG_TO_PTR(s->control_pid))) < 0)
+                                        goto fail;
+
+                        if ((r = cgroup_bonding_kill_list(UNIT(s)->cgroup_bondings, sig, true, pid_set)) < 0) {
+                                if (r != -EAGAIN && r != -ESRCH && r != -ENOENT)
+                                        log_warning("Failed to kill control group: %s", strerror(-r));
+                        } else if (r > 0)
+                                wait_for_exit = true;
+
+                        set_free(pid_set);
+                        pid_set = NULL;
+                }
+        }
+
+        if (wait_for_exit) {
+                if ((r = unit_watch_timer(UNIT(s), s->timeout_usec, &s->timer_watch)) < 0)
+                        goto fail;
+
+                swap_set_state(s, state);
+        } else
+                swap_enter_dead(s, SWAP_SUCCESS);
+
+        return;
+
+fail:
+        log_warning("%s failed to kill processes: %s", UNIT(s)->id, strerror(-r));
+
+        swap_enter_dead(s, SWAP_FAILURE_RESOURCES);
+
+        if (pid_set)
+                set_free(pid_set);
+}
+
+static void swap_enter_activating(Swap *s) {
+        int r, priority;
+
+        assert(s);
+
+        s->control_command_id = SWAP_EXEC_ACTIVATE;
+        s->control_command = s->exec_command + SWAP_EXEC_ACTIVATE;
+
+        if (s->from_fragment)
+                priority = s->parameters_fragment.priority;
+        else if (s->from_etc_fstab)
+                priority = s->parameters_etc_fstab.priority;
+        else
+                priority = -1;
+
+        if (priority >= 0) {
+                char p[LINE_MAX];
+
+                snprintf(p, sizeof(p), "%i", priority);
+                char_array_0(p);
+
+                r = exec_command_set(
+                                s->control_command,
+                                "/sbin/swapon",
+                                "-p",
+                                p,
+                                s->what,
+                                NULL);
+        } else
+                r = exec_command_set(
+                                s->control_command,
+                                "/sbin/swapon",
+                                s->what,
+                                NULL);
+
+        if (r < 0)
+                goto fail;
+
+        swap_unwatch_control_pid(s);
+
+        if ((r = swap_spawn(s, s->control_command, &s->control_pid)) < 0)
+                goto fail;
+
+        swap_set_state(s, SWAP_ACTIVATING);
+
+        return;
+
+fail:
+        log_warning("%s failed to run 'swapon' task: %s", UNIT(s)->id, strerror(-r));
+        swap_enter_dead(s, SWAP_FAILURE_RESOURCES);
+}
+
+static void swap_enter_deactivating(Swap *s) {
+        int r;
+
+        assert(s);
+
+        s->control_command_id = SWAP_EXEC_DEACTIVATE;
+        s->control_command = s->exec_command + SWAP_EXEC_DEACTIVATE;
+
+        if ((r = exec_command_set(
+                             s->control_command,
+                             "/sbin/swapoff",
+                             s->what,
+                             NULL)) < 0)
+                goto fail;
+
+        swap_unwatch_control_pid(s);
+
+        if ((r = swap_spawn(s, s->control_command, &s->control_pid)) < 0)
+                goto fail;
+
+        swap_set_state(s, SWAP_DEACTIVATING);
+
+        return;
+
+fail:
+        log_warning("%s failed to run 'swapoff' task: %s", UNIT(s)->id, strerror(-r));
+        swap_enter_active(s, SWAP_FAILURE_RESOURCES);
+}
+
+static int swap_start(Unit *u) {
+        Swap *s = SWAP(u);
+
+        assert(s);
+
+        /* We cannot fulfill this request right now, try again later
+         * please! */
+
+        if (s->state == SWAP_DEACTIVATING ||
+            s->state == SWAP_DEACTIVATING_SIGTERM ||
+            s->state == SWAP_DEACTIVATING_SIGKILL ||
+            s->state == SWAP_ACTIVATING_SIGTERM ||
+            s->state == SWAP_ACTIVATING_SIGKILL)
+                return -EAGAIN;
+
+        if (s->state == SWAP_ACTIVATING)
+                return 0;
+
+        assert(s->state == SWAP_DEAD || s->state == SWAP_FAILED);
+
+        s->result = SWAP_SUCCESS;
+        swap_enter_activating(s);
+        return 0;
+}
+
+static int swap_stop(Unit *u) {
+        Swap *s = SWAP(u);
+
+        assert(s);
+
+        if (s->state == SWAP_DEACTIVATING ||
+            s->state == SWAP_DEACTIVATING_SIGTERM ||
+            s->state == SWAP_DEACTIVATING_SIGKILL ||
+            s->state == SWAP_ACTIVATING_SIGTERM ||
+            s->state == SWAP_ACTIVATING_SIGKILL)
+                return 0;
+
+        assert(s->state == SWAP_ACTIVATING ||
+               s->state == SWAP_ACTIVE);
+
+        swap_enter_deactivating(s);
+        return 0;
+}
+
+static int swap_serialize(Unit *u, FILE *f, FDSet *fds) {
+        Swap *s = SWAP(u);
+
+        assert(s);
+        assert(f);
+        assert(fds);
+
+        unit_serialize_item(u, f, "state", swap_state_to_string(s->state));
+        unit_serialize_item(u, f, "result", swap_result_to_string(s->result));
+
+        if (s->control_pid > 0)
+                unit_serialize_item_format(u, f, "control-pid", "%lu", (unsigned long) s->control_pid);
+
+        if (s->control_command_id >= 0)
+                unit_serialize_item(u, f, "control-command", swap_exec_command_to_string(s->control_command_id));
+
+        return 0;
+}
+
+static int swap_deserialize_item(Unit *u, const char *key, const char *value, FDSet *fds) {
+        Swap *s = SWAP(u);
+
+        assert(s);
+        assert(fds);
+
+        if (streq(key, "state")) {
+                SwapState state;
+
+                if ((state = swap_state_from_string(value)) < 0)
+                        log_debug("Failed to parse state value %s", value);
+                else
+                        s->deserialized_state = state;
+        } else if (streq(key, "result")) {
+                SwapResult f;
+
+                f = swap_result_from_string(value);
+                if (f < 0)
+                        log_debug("Failed to parse result value %s", value);
+                else if (f != SWAP_SUCCESS)
+                        s->result = f;
+        } else if (streq(key, "control-pid")) {
+                pid_t pid;
+
+                if (parse_pid(value, &pid) < 0)
+                        log_debug("Failed to parse control-pid value %s", value);
+                else
+                        s->control_pid = pid;
+
+        } else if (streq(key, "control-command")) {
+                SwapExecCommand id;
+
+                if ((id = swap_exec_command_from_string(value)) < 0)
+                        log_debug("Failed to parse exec-command value %s", value);
+                else {
+                        s->control_command_id = id;
+                        s->control_command = s->exec_command + id;
+                }
+
+        } else
+                log_debug("Unknown serialization key '%s'", key);
+
+        return 0;
+}
+
+static UnitActiveState swap_active_state(Unit *u) {
+        assert(u);
+
+        return state_translation_table[SWAP(u)->state];
+}
+
+static const char *swap_sub_state_to_string(Unit *u) {
+        assert(u);
+
+        return swap_state_to_string(SWAP(u)->state);
+}
+
+static bool swap_check_gc(Unit *u) {
+        Swap *s = SWAP(u);
+
+        assert(s);
+
+        return s->from_etc_fstab || s->from_proc_swaps;
+}
+
+static void swap_sigchld_event(Unit *u, pid_t pid, int code, int status) {
+        Swap *s = SWAP(u);
+        SwapResult f;
+
+        assert(s);
+        assert(pid >= 0);
+
+        if (pid != s->control_pid)
+                return;
+
+        s->control_pid = 0;
+
+        if (is_clean_exit(code, status))
+                f = SWAP_SUCCESS;
+        else if (code == CLD_EXITED)
+                f = SWAP_FAILURE_EXIT_CODE;
+        else if (code == CLD_KILLED)
+                f = SWAP_FAILURE_SIGNAL;
+        else if (code == CLD_DUMPED)
+                f = SWAP_FAILURE_CORE_DUMP;
+        else
+                assert_not_reached("Unknown code");
+
+        if (f != SWAP_SUCCESS)
+                s->result = f;
+
+        if (s->control_command) {
+                exec_status_exit(&s->control_command->exec_status, &s->exec_context, pid, code, status);
+
+                s->control_command = NULL;
+                s->control_command_id = _SWAP_EXEC_COMMAND_INVALID;
+        }
+
+        log_full(f == SWAP_SUCCESS ? LOG_DEBUG : LOG_NOTICE,
+                 "%s swap process exited, code=%s status=%i", u->id, sigchld_code_to_string(code), status);
+
+        switch (s->state) {
+
+        case SWAP_ACTIVATING:
+        case SWAP_ACTIVATING_SIGTERM:
+        case SWAP_ACTIVATING_SIGKILL:
+
+                if (f == SWAP_SUCCESS)
+                        swap_enter_active(s, f);
+                else
+                        swap_enter_dead(s, f);
+                break;
+
+        case SWAP_DEACTIVATING:
+        case SWAP_DEACTIVATING_SIGKILL:
+        case SWAP_DEACTIVATING_SIGTERM:
+
+                if (f == SWAP_SUCCESS)
+                        swap_enter_dead(s, f);
+                else
+                        swap_enter_dead(s, 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);
+
+        /* Request a reload of /proc/swaps, so that following units
+         * can follow our state change */
+        u->manager->request_reload = true;
+}
+
+static void swap_timer_event(Unit *u, uint64_t elapsed, Watch *w) {
+        Swap *s = SWAP(u);
+
+        assert(s);
+        assert(elapsed == 1);
+        assert(w == &s->timer_watch);
+
+        switch (s->state) {
+
+        case SWAP_ACTIVATING:
+                log_warning("%s activation timed out. Stopping.", u->id);
+                swap_enter_signal(s, SWAP_ACTIVATING_SIGTERM, SWAP_FAILURE_TIMEOUT);
+                break;
+
+        case SWAP_DEACTIVATING:
+                log_warning("%s deactivation timed out. Stopping.", u->id);
+                swap_enter_signal(s, SWAP_DEACTIVATING_SIGTERM, SWAP_FAILURE_TIMEOUT);
+                break;
+
+        case SWAP_ACTIVATING_SIGTERM:
+                if (s->exec_context.send_sigkill) {
+                        log_warning("%s activation timed out. Killing.", u->id);
+                        swap_enter_signal(s, SWAP_ACTIVATING_SIGKILL, SWAP_FAILURE_TIMEOUT);
+                } else {
+                        log_warning("%s activation timed out. Skipping SIGKILL. Ignoring.", u->id);
+                        swap_enter_dead(s, SWAP_FAILURE_TIMEOUT);
+                }
+                break;
+
+        case SWAP_DEACTIVATING_SIGTERM:
+                if (s->exec_context.send_sigkill) {
+                        log_warning("%s deactivation timed out. Killing.", u->id);
+                        swap_enter_signal(s, SWAP_DEACTIVATING_SIGKILL, SWAP_FAILURE_TIMEOUT);
+                } else {
+                        log_warning("%s deactivation timed out. Skipping SIGKILL. Ignoring.", u->id);
+                        swap_enter_dead(s, SWAP_FAILURE_TIMEOUT);
+                }
+                break;
+
+        case SWAP_ACTIVATING_SIGKILL:
+        case SWAP_DEACTIVATING_SIGKILL:
+                log_warning("%s swap process still around after SIGKILL. Ignoring.", u->id);
+                swap_enter_dead(s, SWAP_FAILURE_TIMEOUT);
+                break;
+
+        default:
+                assert_not_reached("Timeout at wrong time.");
+        }
+}
+
+static int swap_load_proc_swaps(Manager *m, bool set_flags) {
+        unsigned i;
+        int r = 0;
+
+        assert(m);
+
+        rewind(m->proc_swaps);
+
+        (void) fscanf(m->proc_swaps, "%*s %*s %*s %*s %*s\n");
+
+        for (i = 1;; i++) {
+                char *dev = NULL, *d;
+                int prio = 0, k;
+
+                if ((k = fscanf(m->proc_swaps,
+                                "%ms "  /* device/file */
+                                "%*s "  /* type of swap */
+                                "%*s "  /* swap size */
+                                "%*s "  /* used */
+                                "%i\n", /* priority */
+                                &dev, &prio)) != 2) {
+
+                        if (k == EOF)
+                                break;
+
+                        log_warning("Failed to parse /proc/swaps:%u.", i);
+                        free(dev);
+                        continue;
+                }
+
+                d = cunescape(dev);
+                free(dev);
+
+                if (!d)
+                        return -ENOMEM;
+
+                k = swap_process_new_swap(m, d, prio, set_flags);
+                free(d);
+
+                if (k < 0)
+                        r = k;
+        }
+
+        return r;
+}
+
+int swap_dispatch_reload(Manager *m) {
+        /* This function should go as soon as the kernel properly notifies us */
+
+        if (_likely_(!m->request_reload))
+                return 0;
+
+        m->request_reload = false;
+
+        return swap_fd_event(m, EPOLLPRI);
+}
+
+int swap_fd_event(Manager *m, int events) {
+        Unit *u;
+        int r;
+
+        assert(m);
+        assert(events & EPOLLPRI);
+
+        if ((r = swap_load_proc_swaps(m, true)) < 0) {
+                log_error("Failed to reread /proc/swaps: %s", strerror(-r));
+
+                /* Reset flags, just in case, for late calls */
+                LIST_FOREACH(units_by_type, u, m->units_by_type[UNIT_SWAP]) {
+                        Swap *swap = SWAP(u);
+
+                        swap->is_active = swap->just_activated = false;
+                }
+
+                return 0;
+        }
+
+        manager_dispatch_load_queue(m);
+
+        LIST_FOREACH(units_by_type, u, m->units_by_type[UNIT_SWAP]) {
+                Swap *swap = SWAP(u);
+
+                if (!swap->is_active) {
+                        /* This has just been deactivated */
+
+                        swap->from_proc_swaps = false;
+                        swap_unset_proc_swaps(swap);
+
+                        switch (swap->state) {
+
+                        case SWAP_ACTIVE:
+                                swap_enter_dead(swap, SWAP_SUCCESS);
+                                break;
+
+                        default:
+                                swap_set_state(swap, swap->state);
+                                break;
+                        }
+
+                } else if (swap->just_activated) {
+
+                        /* New swap entry */
+
+                        switch (swap->state) {
+
+                        case SWAP_DEAD:
+                        case SWAP_FAILED:
+                                swap_enter_active(swap, SWAP_SUCCESS);
+                                break;
+
+                        default:
+                                /* Nothing really changed, but let's
+                                 * issue an notification call
+                                 * nonetheless, in case somebody is
+                                 * waiting for this. */
+                                swap_set_state(swap, swap->state);
+                                break;
+                        }
+                }
+
+                /* Reset the flags for later calls */
+                swap->is_active = swap->just_activated = false;
+        }
+
+        return 1;
+}
+
+static Unit *swap_following(Unit *u) {
+        Swap *s = SWAP(u);
+        Swap *other, *first = NULL;
+
+        assert(s);
+
+        if (streq_ptr(s->what, s->parameters_proc_swaps.what))
+                return NULL;
+
+        /* Make everybody follow the unit that's named after the swap
+         * device in the kernel */
+
+        LIST_FOREACH_AFTER(same_proc_swaps, other, s)
+                if (streq_ptr(other->what, other->parameters_proc_swaps.what))
+                        return UNIT(other);
+
+        LIST_FOREACH_BEFORE(same_proc_swaps, other, s) {
+                if (streq_ptr(other->what, other->parameters_proc_swaps.what))
+                        return UNIT(other);
+
+                first = other;
+        }
+
+        return UNIT(first);
+}
+
+static int swap_following_set(Unit *u, Set **_set) {
+        Swap *s = SWAP(u);
+        Swap *other;
+        Set *set;
+        int r;
+
+        assert(s);
+        assert(_set);
+
+        if (LIST_JUST_US(same_proc_swaps, s)) {
+                *_set = NULL;
+                return 0;
+        }
+
+        if (!(set = set_new(NULL, NULL)))
+                return -ENOMEM;
+
+        LIST_FOREACH_AFTER(same_proc_swaps, other, s)
+                if ((r = set_put(set, other)) < 0)
+                        goto fail;
+
+        LIST_FOREACH_BEFORE(same_proc_swaps, other, s)
+                if ((r = set_put(set, other)) < 0)
+                        goto fail;
+
+        *_set = set;
+        return 1;
+
+fail:
+        set_free(set);
+        return r;
+}
+
+static void swap_shutdown(Manager *m) {
+        assert(m);
+
+        if (m->proc_swaps) {
+                fclose(m->proc_swaps);
+                m->proc_swaps = NULL;
+        }
+
+        hashmap_free(m->swaps_by_proc_swaps);
+        m->swaps_by_proc_swaps = NULL;
+}
+
+static int swap_enumerate(Manager *m) {
+        int r;
+        struct epoll_event ev;
+        assert(m);
+
+        if (!m->proc_swaps) {
+                if (!(m->proc_swaps = fopen("/proc/swaps", "re")))
+                        return (errno == ENOENT) ? 0 : -errno;
+
+                m->swap_watch.type = WATCH_SWAP;
+                m->swap_watch.fd = fileno(m->proc_swaps);
+
+                zero(ev);
+                ev.events = EPOLLPRI;
+                ev.data.ptr = &m->swap_watch;
+
+                if (epoll_ctl(m->epoll_fd, EPOLL_CTL_ADD, m->swap_watch.fd, &ev) < 0)
+                        return -errno;
+        }
+
+        /* We rely on mount.c to load /etc/fstab for us */
+
+        if ((r = swap_load_proc_swaps(m, false)) < 0)
+                swap_shutdown(m);
+
+        return r;
+}
+
+static void swap_reset_failed(Unit *u) {
+        Swap *s = SWAP(u);
+
+        assert(s);
+
+        if (s->state == SWAP_FAILED)
+                swap_set_state(s, SWAP_DEAD);
+
+        s->result = SWAP_SUCCESS;
+}
+
+static int swap_kill(Unit *u, KillWho who, KillMode mode, int signo, DBusError *error) {
+        Swap *s = SWAP(u);
+        int r = 0;
+        Set *pid_set = NULL;
+
+        assert(s);
+
+        if (who == KILL_MAIN) {
+                dbus_set_error(error, BUS_ERROR_NO_SUCH_PROCESS, "Swap units have no main processes");
+                return -ESRCH;
+        }
+
+        if (s->control_pid <= 0 && who == KILL_CONTROL) {
+                dbus_set_error(error, BUS_ERROR_NO_SUCH_PROCESS, "No control process to kill");
+                return -ESRCH;
+        }
+
+        if (who == KILL_CONTROL || who == KILL_ALL)
+                if (s->control_pid > 0)
+                        if (kill(s->control_pid, signo) < 0)
+                                r = -errno;
+
+        if (who == KILL_ALL && mode == KILL_CONTROL_GROUP) {
+                int q;
+
+                if (!(pid_set = set_new(trivial_hash_func, trivial_compare_func)))
+                        return -ENOMEM;
+
+                /* Exclude the control pid from being killed via the cgroup */
+                if (s->control_pid > 0)
+                        if ((q = set_put(pid_set, LONG_TO_PTR(s->control_pid))) < 0) {
+                                r = q;
+                                goto finish;
+                        }
+
+                if ((q = cgroup_bonding_kill_list(UNIT(s)->cgroup_bondings, signo, false, pid_set)) < 0)
+                        if (q != -EAGAIN && q != -ESRCH && q != -ENOENT)
+                                r = q;
+        }
+
+finish:
+        if (pid_set)
+                set_free(pid_set);
+
+        return r;
+}
+
+static const char* const swap_state_table[_SWAP_STATE_MAX] = {
+        [SWAP_DEAD] = "dead",
+        [SWAP_ACTIVATING] = "activating",
+        [SWAP_ACTIVE] = "active",
+        [SWAP_DEACTIVATING] = "deactivating",
+        [SWAP_ACTIVATING_SIGTERM] = "activating-sigterm",
+        [SWAP_ACTIVATING_SIGKILL] = "activating-sigkill",
+        [SWAP_DEACTIVATING_SIGTERM] = "deactivating-sigterm",
+        [SWAP_DEACTIVATING_SIGKILL] = "deactivating-sigkill",
+        [SWAP_FAILED] = "failed"
+};
+
+DEFINE_STRING_TABLE_LOOKUP(swap_state, SwapState);
+
+static const char* const swap_exec_command_table[_SWAP_EXEC_COMMAND_MAX] = {
+        [SWAP_EXEC_ACTIVATE] = "ExecActivate",
+        [SWAP_EXEC_DEACTIVATE] = "ExecDeactivate",
+};
+
+DEFINE_STRING_TABLE_LOOKUP(swap_exec_command, SwapExecCommand);
+
+static const char* const swap_result_table[_SWAP_RESULT_MAX] = {
+        [SWAP_SUCCESS] = "success",
+        [SWAP_FAILURE_RESOURCES] = "resources",
+        [SWAP_FAILURE_TIMEOUT] = "timeout",
+        [SWAP_FAILURE_EXIT_CODE] = "exit-code",
+        [SWAP_FAILURE_SIGNAL] = "signal",
+        [SWAP_FAILURE_CORE_DUMP] = "core-dump"
+};
+
+DEFINE_STRING_TABLE_LOOKUP(swap_result, SwapResult);
+
+const UnitVTable swap_vtable = {
+        .suffix = ".swap",
+        .object_size = sizeof(Swap),
+        .sections =
+                "Unit\0"
+                "Swap\0"
+                "Install\0",
+
+        .no_alias = true,
+        .no_instances = true,
+        .show_status = true,
+
+        .init = swap_init,
+        .load = swap_load,
+        .done = swap_done,
+
+        .coldplug = swap_coldplug,
+
+        .dump = swap_dump,
+
+        .start = swap_start,
+        .stop = swap_stop,
+
+        .kill = swap_kill,
+
+        .serialize = swap_serialize,
+        .deserialize_item = swap_deserialize_item,
+
+        .active_state = swap_active_state,
+        .sub_state_to_string = swap_sub_state_to_string,
+
+        .check_gc = swap_check_gc,
+
+        .sigchld_event = swap_sigchld_event,
+        .timer_event = swap_timer_event,
+
+        .reset_failed = swap_reset_failed,
+
+        .bus_interface = "org.freedesktop.systemd1.Swap",
+        .bus_message_handler = bus_swap_message_handler,
+        .bus_invalidating_properties =  bus_swap_invalidating_properties,
+
+        .following = swap_following,
+        .following_set = swap_following_set,
+
+        .enumerate = swap_enumerate,
+        .shutdown = swap_shutdown
+};