picnoir
/
Systemd
1
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity
Systemd/src/swap.c

1329 lines
39 KiB
C
Raw Blame History

/*-*- 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"
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(s->meta.manager->swaps_by_proc_swaps, s->parameters_proc_swaps.what);
LIST_REMOVE(Swap, same_proc_swaps, first, s);
if (first)
hashmap_remove_and_replace(s->meta.manager->swaps_by_proc_swaps, s->parameters_proc_swaps.what, first->parameters_proc_swaps.what, first);
else
hashmap_remove(s->meta.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(s->meta.load_state == UNIT_STUB);
s->timeout_usec = DEFAULT_TIMEOUT_USEC;
exec_context_init(&s->exec_context);
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 = _MOUNT_EXEC_COMMAND_INVALID;
}
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 (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->swap_auto) &&
s->from_etc_fstab &&
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_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;
return unit_add_node_link(UNIT(s), s->what,
!p->noauto && p->nofail &&
s->meta.manager->running_as == MANAGER_SYSTEM);
}
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;
if ((r = unit_add_two_dependencies_by_name(UNIT(s), UNIT_BEFORE, UNIT_CONFLICTED_BY, SPECIAL_UMOUNT_TARGET, NULL, true)) < 0)
return r;
}
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;
}
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.", 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 = 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_cgroup(u)) < 0)
return r;
if (s->meta.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);
if (!(e = unit_name_from_path(what, ".swap")))
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;
if (!(u = unit_new(m))) {
free(e);
return -ENOMEM;
}
if ((r = unit_add_name(u, e)) < 0)
goto fail;
if (!(SWAP(u)->what = strdup(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",
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;
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"
"%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, 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,
s->meta.manager->environment,
true,
true,
true,
s->meta.manager->confirm_spawn,
s->meta.cgroup_bondings,
&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, bool success) {
assert(s);
if (!success)
s->failure = true;
swap_set_state(s, s->failure ? SWAP_FAILED : SWAP_DEAD);
}
static void swap_enter_active(Swap *s, bool success) {
assert(s);
if (!success)
s->failure = true;
swap_set_state(s, SWAP_ACTIVE);
}
static void swap_enter_signal(Swap *s, SwapState state, bool success) {
int r;
Set *pid_set = NULL;
bool wait_for_exit = false;
assert(s);
if (!success)
s->failure = true;
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(s->exec_context.kill_mode == KILL_PROCESS_GROUP ?
-s->control_pid :
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(s->meta.cgroup_bondings, sig, 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);
}
}
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, true);
return;
fail:
log_warning("%s failed to kill processes: %s", s->meta.id, strerror(-r));
swap_enter_dead(s, false);
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", s->meta.id, strerror(-r));
swap_enter_dead(s, false);
}
static void swap_enter_deactivating(Swap *s, bool success) {
int r;
assert(s);
if (!success)
s->failure = true;
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", s->meta.id, strerror(-r));
swap_enter_active(s, false);
}
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->failure = false;
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, true);
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, "failure", yes_no(s->failure));
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, "failure")) {
int b;
if ((b = parse_boolean(value)) < 0)
log_debug("Failed to parse failure value %s", value);
else
s->failure = b || s->failure;
} 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);
bool success;
assert(s);
assert(pid >= 0);
if (pid != s->control_pid)
return;
s->control_pid = 0;
success = is_clean_exit(code, status);
s->failure = s->failure || !success;
if (s->control_command) {
exec_status_exit(&s->control_command->exec_status, pid, code, status, s->exec_context.utmp_id);
s->control_command = NULL;
s->control_command_id = _SWAP_EXEC_COMMAND_INVALID;
}
log_full(success ? LOG_DEBUG : LOG_NOTICE,
"%s swap process exited, code=%s status=%i", u->meta.id, sigchld_code_to_string(code), status);
switch (s->state) {
case SWAP_ACTIVATING:
case SWAP_ACTIVATING_SIGTERM:
case SWAP_ACTIVATING_SIGKILL:
if (success)
swap_enter_active(s, true);
else
swap_enter_dead(s, false);
break;
case SWAP_DEACTIVATING:
case SWAP_DEACTIVATING_SIGKILL:
case SWAP_DEACTIVATING_SIGTERM:
if (success)
swap_enter_dead(s, true);
else
swap_enter_dead(s, false);
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->meta.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->meta.id);
swap_enter_signal(s, SWAP_ACTIVATING_SIGTERM, false);
break;
case SWAP_DEACTIVATING:
log_warning("%s deactivation timed out. Stopping.", u->meta.id);
swap_enter_signal(s, SWAP_DEACTIVATING_SIGTERM, false);
break;
case SWAP_ACTIVATING_SIGTERM:
log_warning("%s activation timed out. Killing.", u->meta.id);
swap_enter_signal(s, SWAP_ACTIVATING_SIGKILL, false);
break;
case SWAP_DEACTIVATING_SIGTERM:
log_warning("%s deactivation timed out. Killing.", u->meta.id);
swap_enter_signal(s, SWAP_DEACTIVATING_SIGKILL, false);
break;
case SWAP_ACTIVATING_SIGKILL:
case SWAP_DEACTIVATING_SIGKILL:
log_warning("%s swap process still around after SIGKILL. Ignoring.", u->meta.id);
swap_enter_dead(s, false);
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) {
Meta *meta;
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_per_type, meta, m->units_per_type[UNIT_SWAP]) {
Swap *swap = (Swap*) meta;
swap->is_active = swap->just_activated = false;
}
return 0;
}
manager_dispatch_load_queue(m);
LIST_FOREACH(units_per_type, meta, m->units_per_type[UNIT_SWAP]) {
Swap *swap = (Swap*) meta;
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, true);
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, true);
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 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;
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->failure = false;
}
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 -EINVAL;
}
if (s->control_pid <= 0 && who == KILL_CONTROL) {
dbus_set_error(error, BUS_ERROR_NO_SUCH_PROCESS, "No control process to kill");
return -ENOENT;
}
if (s->control_pid > 0)
if (kill(mode == KILL_PROCESS_GROUP ? -s->control_pid : s->control_pid, signo) < 0)
r = -errno;
if (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(s->meta.cgroup_bondings, signo, pid_set)) < 0)
if (r != -EAGAIN && r != -ESRCH && r != -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);
const UnitVTable swap_vtable = {
.suffix = ".swap",
.no_alias = true,
.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,
.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,
.enumerate = swap_enumerate,
.shutdown = swap_shutdown
};
Reference in New Issue View Git Blame Copy Permalink