/*-*- Mode: C; c-basic-offset: 8 -*-*/ /*** 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 "unit.h" #include "swap.h" #include "load-fragment.h" #include "load-dropin.h" #include "unit-name.h" #include "dbus-swap.h" #include "special.h" static const UnitActiveState state_translation_table[_SWAP_STATE_MAX] = { [SWAP_DEAD] = UNIT_INACTIVE, [SWAP_ACTIVE] = UNIT_ACTIVE, [SWAP_MAINTENANCE] = UNIT_MAINTENANCE }; static void swap_init(Unit *u) { Swap *s = SWAP(u); assert(s); assert(s->meta.load_state == UNIT_STUB); s->parameters_etc_fstab.priority = s->parameters_proc_swaps.priority = s->parameters_fragment.priority = -1; } static void swap_done(Unit *u) { Swap *s = SWAP(u); assert(s); free(s->what); free(s->parameters_etc_fstab.what); free(s->parameters_proc_swaps.what); free(s->parameters_fragment.what); } int swap_add_one_mount_link(Swap *s, Mount *m) { int r; assert(s); assert(m); if (s->meta.load_state != UNIT_LOADED || m->meta.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) { Meta *other; int r; assert(s); LIST_FOREACH(units_per_type, other, s->meta.manager->units_per_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(s->meta.manager, SPECIAL_SWAP_TARGET, NULL, NULL, &tu)) < 0) return r; if (!p->noauto && p->handle && s->meta.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_default_dependencies(Swap *s) { int r; assert(s); if (s->meta.manager->running_as == MANAGER_SYSTEM) { if ((r = unit_add_dependency_by_name(UNIT(s), UNIT_AFTER, SPECIAL_SYSINIT_TARGET, NULL, true)) < 0) return r; /* Note that by default we don't disable swap devices * on shutdown. i.e. there is no umount.target * conflicts here. */ } return 0; } static int swap_verify(Swap *s) { bool b; char *e; if (s->meta.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", s->meta.id); return -EINVAL; } return 0; } static int swap_load(Unit *u) { int r; Swap *s = SWAP(u); assert(s); assert(u->meta.load_state == UNIT_STUB); /* Load a .swap file */ if ((r = unit_load_fragment_and_dropin_optional(u)) < 0) return r; if (u->meta.load_state == UNIT_LOADED) { if (s->meta.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->meta.id); if (!s->what) return -ENOMEM; } path_kill_slashes(s->what); if (!s->meta.description) if ((r = unit_set_description(u, s->what)) < 0) return r; if ((r = unit_add_node_link(u, s->what, u->meta.manager->running_as == MANAGER_SYSTEM)) < 0) return r; if ((r = swap_add_mount_links(s)) < 0) return r; if ((r = swap_add_target_links(s)) < 0) return r; if (s->meta.default_dependencies) if ((r = swap_add_default_dependencies(s)) < 0) return r; } return swap_verify(s); } static int swap_find(Manager *m, const char *what, Unit **_u) { Unit *u; char *e; assert(m); assert(what); assert(_u); /* /proc/swaps and /etc/fstab might refer to this device by * different names (e.g. one by uuid, the other by the kernel * name), we hence need to look for all aliases we are aware * of for this device */ if (!(e = unit_name_from_path(what, ".device"))) return -ENOMEM; u = manager_get_unit(m, e); free(e); if (u) { Iterator i; const char *d; SET_FOREACH(d, u->meta.names, i) { Unit *k; if (!(e = unit_name_change_suffix(d, ".swap"))) return -ENOMEM; k = manager_get_unit(m, e); free(e); if (k) { *_u = k; return 0; } } } *_u = NULL; return 0; } int swap_add_one( Manager *m, const char *what, int priority, bool noauto, bool handle, bool from_proc_swaps) { Unit *u = NULL; char *e = NULL, *w = NULL; bool delete = false; int r; SwapParameters *p; assert(m); assert(what); if (!(e = unit_name_from_path(what, ".swap"))) return -ENOMEM; if (!(u = manager_get_unit(m, e))) if ((r = swap_find(m, what, &u)) < 0) goto fail; if (!u) { delete = true; if (!(u = unit_new(m))) { free(e); return -ENOMEM; } } else delete = false; if ((r = unit_add_name(u, e)) < 0) goto fail; if (!(w = strdup(what))) { r = -ENOMEM; goto fail; } if (from_proc_swaps) { p = &SWAP(u)->parameters_proc_swaps; SWAP(u)->from_proc_swaps = true; } else { p = &SWAP(u)->parameters_etc_fstab; SWAP(u)->from_etc_fstab = true; } free(p->what); p->what = w; p->priority = priority; p->noauto = noauto; p->handle = handle; if (delete) unit_add_to_load_queue(u); unit_add_to_dbus_queue(u); free(e); return 0; fail: free(w); free(e); if (delete && u) unit_free(u); 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 != old_state) log_debug("%s changed %s -> %s", s->meta.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]); } static int swap_coldplug(Unit *u) { Swap *s = SWAP(u); SwapState new_state = SWAP_DEAD; 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) 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" "%sWhat: %s\n" "%sPriority: %i\n" "%sNoAuto: %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, s->what, prefix, p->priority, prefix, yes_no(p->noauto), 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)); } static void swap_enter_dead(Swap *s, bool success) { assert(s); swap_set_state(s, success ? SWAP_MAINTENANCE : SWAP_DEAD); } static int swap_start(Unit *u) { Swap *s = SWAP(u); int priority = -1; int r; assert(s); assert(s->state == SWAP_DEAD || s->state == SWAP_MAINTENANCE); if (s->from_fragment) priority = s->parameters_fragment.priority; else if (s->from_etc_fstab) priority = s->parameters_etc_fstab.priority; r = swapon(s->what, (priority << SWAP_FLAG_PRIO_SHIFT) & SWAP_FLAG_PRIO_MASK); if (r < 0 && errno != EBUSY) { r = -errno; swap_enter_dead(s, false); return r; } swap_set_state(s, SWAP_ACTIVE); return 0; } static int swap_stop(Unit *u) { Swap *s = SWAP(u); int r; assert(s); assert(s->state == SWAP_ACTIVE); r = swapoff(s->what); swap_enter_dead(s, r >= 0 || errno == EINVAL); 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)); 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 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 int swap_load_proc_swaps(Manager *m) { rewind(m->proc_swaps); (void) fscanf(m->proc_swaps, "%*s %*s %*s %*s %*s\n"); for (;;) { 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; free(dev); return -EBADMSG; } d = cunescape(dev); free(dev); if (!d) return -ENOMEM; k = swap_add_one(m, d, prio, false, false, true); free(d); if (k < 0) return k; } return 0; } static void swap_shutdown(Manager *m) { assert(m); if (m->proc_swaps) { fclose(m->proc_swaps); m->proc_swaps = NULL; } } static int swap_enumerate(Manager *m) { int r; assert(m); if (!m->proc_swaps) if (!(m->proc_swaps = fopen("/proc/swaps", "re"))) return -errno; if ((r = swap_load_proc_swaps(m)) < 0) swap_shutdown(m); return r; } static void swap_reset_maintenance(Unit *u) { Swap *s = SWAP(u); assert(s); if (s->state == SWAP_MAINTENANCE) swap_set_state(s, SWAP_DEAD); } static const char* const swap_state_table[_SWAP_STATE_MAX] = { [SWAP_DEAD] = "dead", [SWAP_ACTIVE] = "active", [SWAP_MAINTENANCE] = "maintenance" }; DEFINE_STRING_TABLE_LOOKUP(swap_state, SwapState); const UnitVTable swap_vtable = { .suffix = ".swap", .no_instances = true, .no_isolate = 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, .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, .bus_message_handler = bus_swap_message_handler, .reset_maintenance = swap_reset_maintenance, .enumerate = swap_enumerate, .shutdown = swap_shutdown };