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systemd/src/core/automount.c
michaelolbrich 0a62f81045 automount: handle expire_tokens when the mount unit changes its state (#3434) 
This basically reverts 7b2fd9d512 ("core:
remove duplicate code in automount_update_mount()").

This was not duplicate code. The expire_tokens need to be handled as well:
Send 0 == success for MOUNT_DEAD (umount successful), do nothing for
MOUNT_UNMOUNTING (not yet done) and an error for everything else.

Otherwise the automount logic will assume unmounting is not done and will
not send any new requests for mounting. As a result, the corresponding
mount unit is never mounted.

Without this, automounts with TimeoutIdleSec= are broken. Once the idle
timeout triggered a umount, any access to the corresponding filesystem
hangs forever.

Fixes #3332.
2016-06-05 11:25:14 -04:00

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/***
This file is part of systemd.
Copyright 2010 Lennart Poettering
systemd is free software; you can redistribute it and/or modify it
under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation; either version 2.1 of the License, or
(at your option) any later version.
systemd is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public License
along with systemd; If not, see <http://www.gnu.org/licenses/>.
***/
#include <errno.h>
#include <fcntl.h>
#include <limits.h>
#include <linux/auto_dev-ioctl.h>
#include <linux/auto_fs4.h>
#include <sys/epoll.h>
#include <sys/mount.h>
#include <sys/stat.h>
#include <unistd.h>
#include "alloc-util.h"
#include "async.h"
#include "automount.h"
#include "bus-error.h"
#include "bus-util.h"
#include "dbus-automount.h"
#include "fd-util.h"
#include "formats-util.h"
#include "io-util.h"
#include "label.h"
#include "mkdir.h"
#include "mount-util.h"
#include "mount.h"
#include "parse-util.h"
#include "path-util.h"
#include "process-util.h"
#include "special.h"
#include "stdio-util.h"
#include "string-table.h"
#include "string-util.h"
#include "unit-name.h"
#include "unit.h"
static const UnitActiveState state_translation_table[_AUTOMOUNT_STATE_MAX] = {
[AUTOMOUNT_DEAD] = UNIT_INACTIVE,
[AUTOMOUNT_WAITING] = UNIT_ACTIVE,
[AUTOMOUNT_RUNNING] = UNIT_ACTIVE,
[AUTOMOUNT_FAILED] = UNIT_FAILED
};
struct expire_data {
int dev_autofs_fd;
int ioctl_fd;
};
static inline void expire_data_free(struct expire_data *data) {
if (!data)
return;
safe_close(data->dev_autofs_fd);
safe_close(data->ioctl_fd);
free(data);
}
DEFINE_TRIVIAL_CLEANUP_FUNC(struct expire_data*, expire_data_free);
static int open_dev_autofs(Manager *m);
static int automount_dispatch_io(sd_event_source *s, int fd, uint32_t events, void *userdata);
static int automount_start_expire(Automount *a);
static void automount_stop_expire(Automount *a);
static int automount_send_ready(Automount *a, Set *tokens, int status);
static void automount_init(Unit *u) {
Automount *a = AUTOMOUNT(u);
assert(u);
assert(u->load_state == UNIT_STUB);
a->pipe_fd = -1;
a->directory_mode = 0755;
UNIT(a)->ignore_on_isolate = true;
}
static void unmount_autofs(Automount *a) {
int r;
assert(a);
if (a->pipe_fd < 0)
return;
automount_send_ready(a, a->tokens, -EHOSTDOWN);
automount_send_ready(a, a->expire_tokens, -EHOSTDOWN);
a->pipe_event_source = sd_event_source_unref(a->pipe_event_source);
a->pipe_fd = safe_close(a->pipe_fd);
/* If we reload/reexecute things we keep the mount point
* around */
if (a->where &&
(UNIT(a)->manager->exit_code != MANAGER_RELOAD &&
UNIT(a)->manager->exit_code != MANAGER_REEXECUTE)) {
r = repeat_unmount(a->where, MNT_DETACH);
if (r < 0)
log_error_errno(r, "Failed to unmount: %m");
}
}
static void automount_done(Unit *u) {
Automount *a = AUTOMOUNT(u);
assert(a);
unmount_autofs(a);
a->where = mfree(a->where);
a->tokens = set_free(a->tokens);
a->expire_tokens = set_free(a->expire_tokens);
a->expire_event_source = sd_event_source_unref(a->expire_event_source);
}
static int automount_add_mount_links(Automount *a) {
_cleanup_free_ char *parent = NULL;
assert(a);
parent = dirname_malloc(a->where);
if (!parent)
return -ENOMEM;
return unit_require_mounts_for(UNIT(a), parent);
}
static int automount_add_default_dependencies(Automount *a) {
int r;
assert(a);
if (!UNIT(a)->default_dependencies)
return 0;
if (!MANAGER_IS_SYSTEM(UNIT(a)->manager))
return 0;
r = unit_add_two_dependencies_by_name(UNIT(a), UNIT_BEFORE, UNIT_CONFLICTS, SPECIAL_UMOUNT_TARGET, NULL, true);
if (r < 0)
return r;
return 0;
}
static int automount_verify(Automount *a) {
_cleanup_free_ char *e = NULL;
int r;
assert(a);
if (UNIT(a)->load_state != UNIT_LOADED)
return 0;
if (path_equal(a->where, "/")) {
log_unit_error(UNIT(a), "Cannot have an automount unit for the root directory. Refusing.");
return -EINVAL;
}
r = unit_name_from_path(a->where, ".automount", &e);
if (r < 0)
return log_unit_error(UNIT(a), "Failed to generate unit name from path: %m");
if (!unit_has_name(UNIT(a), e)) {
log_unit_error(UNIT(a), "Where= setting doesn't match unit name. Refusing.");
return -EINVAL;
}
return 0;
}
static int automount_load(Unit *u) {
Automount *a = AUTOMOUNT(u);
int r;
assert(u);
assert(u->load_state == UNIT_STUB);
/* Load a .automount file */
r = unit_load_fragment_and_dropin_optional(u);
if (r < 0)
return r;
if (u->load_state == UNIT_LOADED) {
Unit *x;
if (!a->where) {
r = unit_name_to_path(u->id, &a->where);
if (r < 0)
return r;
}
path_kill_slashes(a->where);
r = unit_load_related_unit(u, ".mount", &x);
if (r < 0)
return r;
r = unit_add_two_dependencies(u, UNIT_BEFORE, UNIT_TRIGGERS, x, true);
if (r < 0)
return r;
r = automount_add_mount_links(a);
if (r < 0)
return r;
r = automount_add_default_dependencies(a);
if (r < 0)
return r;
}
return automount_verify(a);
}
static void automount_set_state(Automount *a, AutomountState state) {
AutomountState old_state;
assert(a);
old_state = a->state;
a->state = state;
if (state != AUTOMOUNT_RUNNING)
automount_stop_expire(a);
if (state != AUTOMOUNT_WAITING &&
state != AUTOMOUNT_RUNNING)
unmount_autofs(a);
if (state != old_state)
log_unit_debug(UNIT(a), "Changed %s -> %s", automount_state_to_string(old_state), automount_state_to_string(state));
unit_notify(UNIT(a), state_translation_table[old_state], state_translation_table[state], true);
}
static int automount_coldplug(Unit *u) {
Automount *a = AUTOMOUNT(u);
int r;
assert(a);
assert(a->state == AUTOMOUNT_DEAD);
if (a->deserialized_state != a->state) {
r = open_dev_autofs(u->manager);
if (r < 0)
return r;
if (a->deserialized_state == AUTOMOUNT_WAITING ||
a->deserialized_state == AUTOMOUNT_RUNNING) {
assert(a->pipe_fd >= 0);
r = sd_event_add_io(u->manager->event, &a->pipe_event_source, a->pipe_fd, EPOLLIN, automount_dispatch_io, u);
if (r < 0)
return r;
(void) sd_event_source_set_description(a->pipe_event_source, "automount-io");
}
automount_set_state(a, a->deserialized_state);
}
return 0;
}
static void automount_dump(Unit *u, FILE *f, const char *prefix) {
char time_string[FORMAT_TIMESPAN_MAX];
Automount *a = AUTOMOUNT(u);
assert(a);
fprintf(f,
"%sAutomount State: %s\n"
"%sResult: %s\n"
"%sWhere: %s\n"
"%sDirectoryMode: %04o\n"
"%sTimeoutIdleUSec: %s\n",
prefix, automount_state_to_string(a->state),
prefix, automount_result_to_string(a->result),
prefix, a->where,
prefix, a->directory_mode,
prefix, format_timespan(time_string, FORMAT_TIMESPAN_MAX, a->timeout_idle_usec, USEC_PER_SEC));
}
static void automount_enter_dead(Automount *a, AutomountResult f) {
assert(a);
if (f != AUTOMOUNT_SUCCESS)
a->result = f;
automount_set_state(a, a->result != AUTOMOUNT_SUCCESS ? AUTOMOUNT_FAILED : AUTOMOUNT_DEAD);
}
static int open_dev_autofs(Manager *m) {
struct autofs_dev_ioctl param;
assert(m);
if (m->dev_autofs_fd >= 0)
return m->dev_autofs_fd;
label_fix("/dev/autofs", false, false);
m->dev_autofs_fd = open("/dev/autofs", O_CLOEXEC|O_RDONLY);
if (m->dev_autofs_fd < 0)
return log_error_errno(errno, "Failed to open /dev/autofs: %m");
init_autofs_dev_ioctl(&param);
if (ioctl(m->dev_autofs_fd, AUTOFS_DEV_IOCTL_VERSION, &param) < 0) {
m->dev_autofs_fd = safe_close(m->dev_autofs_fd);
return -errno;
}
log_debug("Autofs kernel version %i.%i", param.ver_major, param.ver_minor);
return m->dev_autofs_fd;
}
static int open_ioctl_fd(int dev_autofs_fd, const char *where, dev_t devid) {
struct autofs_dev_ioctl *param;
size_t l;
assert(dev_autofs_fd >= 0);
assert(where);
l = sizeof(struct autofs_dev_ioctl) + strlen(where) + 1;
param = alloca(l);
init_autofs_dev_ioctl(param);
param->size = l;
param->ioctlfd = -1;
param->openmount.devid = devid;
strcpy(param->path, where);
if (ioctl(dev_autofs_fd, AUTOFS_DEV_IOCTL_OPENMOUNT, param) < 0)
return -errno;
if (param->ioctlfd < 0)
return -EIO;
(void) fd_cloexec(param->ioctlfd, true);
return param->ioctlfd;
}
static int autofs_protocol(int dev_autofs_fd, int ioctl_fd) {
uint32_t major, minor;
struct autofs_dev_ioctl param;
assert(dev_autofs_fd >= 0);
assert(ioctl_fd >= 0);
init_autofs_dev_ioctl(&param);
param.ioctlfd = ioctl_fd;
if (ioctl(dev_autofs_fd, AUTOFS_DEV_IOCTL_PROTOVER, &param) < 0)
return -errno;
major = param.protover.version;
init_autofs_dev_ioctl(&param);
param.ioctlfd = ioctl_fd;
if (ioctl(dev_autofs_fd, AUTOFS_DEV_IOCTL_PROTOSUBVER, &param) < 0)
return -errno;
minor = param.protosubver.sub_version;
log_debug("Autofs protocol version %i.%i", major, minor);
return 0;
}
static int autofs_set_timeout(int dev_autofs_fd, int ioctl_fd, usec_t usec) {
struct autofs_dev_ioctl param;
assert(dev_autofs_fd >= 0);
assert(ioctl_fd >= 0);
init_autofs_dev_ioctl(&param);
param.ioctlfd = ioctl_fd;
/* Convert to seconds, rounding up. */
param.timeout.timeout = (usec + USEC_PER_SEC - 1) / USEC_PER_SEC;
if (ioctl(dev_autofs_fd, AUTOFS_DEV_IOCTL_TIMEOUT, &param) < 0)
return -errno;
return 0;
}
static int autofs_send_ready(int dev_autofs_fd, int ioctl_fd, uint32_t token, int status) {
struct autofs_dev_ioctl param;
assert(dev_autofs_fd >= 0);
assert(ioctl_fd >= 0);
init_autofs_dev_ioctl(&param);
param.ioctlfd = ioctl_fd;
if (status != 0) {
param.fail.token = token;
param.fail.status = status;
} else
param.ready.token = token;
if (ioctl(dev_autofs_fd, status ? AUTOFS_DEV_IOCTL_FAIL : AUTOFS_DEV_IOCTL_READY, &param) < 0)
return -errno;
return 0;
}
static int automount_send_ready(Automount *a, Set *tokens, int status) {
_cleanup_close_ int ioctl_fd = -1;
unsigned token;
int r;
assert(a);
assert(status <= 0);
if (set_isempty(tokens))
return 0;
ioctl_fd = open_ioctl_fd(UNIT(a)->manager->dev_autofs_fd, a->where, a->dev_id);
if (ioctl_fd < 0)
return ioctl_fd;
if (status != 0)
log_unit_debug_errno(UNIT(a), status, "Sending failure: %m");
else
log_unit_debug(UNIT(a), "Sending success.");
r = 0;
/* Autofs thankfully does not hand out 0 as a token */
while ((token = PTR_TO_UINT(set_steal_first(tokens)))) {
int k;
/* Autofs fun fact II:
*
* if you pass a positive status code here, the kernel will
* freeze! Yay! */
k = autofs_send_ready(UNIT(a)->manager->dev_autofs_fd,
ioctl_fd,
token,
status);
if (k < 0)
r = k;
}
return r;
}
static void automount_trigger_notify(Unit *u, Unit *other) {
Automount *a = AUTOMOUNT(u);
int r;
assert(a);
assert(other);
/* Filter out invocations with bogus state */
if (other->load_state != UNIT_LOADED || other->type != UNIT_MOUNT)
return;
/* Don't propagate state changes from the mount if we are already down */
if (!IN_SET(a->state, AUTOMOUNT_WAITING, AUTOMOUNT_RUNNING))
return;
/* Propagate start limit hit state */
if (other->start_limit_hit) {
automount_enter_dead(a, AUTOMOUNT_FAILURE_MOUNT_START_LIMIT_HIT);
return;
}
/* Don't propagate anything if there's still a job queued */
if (other->job)
return;
/* The mount is successfully established */
if (IN_SET(MOUNT(other)->state, MOUNT_MOUNTED, MOUNT_REMOUNTING)) {
(void) automount_send_ready(a, a->tokens, 0);
r = automount_start_expire(a);
if (r < 0)
log_unit_warning_errno(UNIT(a), r, "Failed to start expiration timer, ignoring: %m");
automount_set_state(a, AUTOMOUNT_RUNNING);
}
if (IN_SET(MOUNT(other)->state,
MOUNT_MOUNTING, MOUNT_MOUNTING_DONE,
MOUNT_MOUNTED, MOUNT_REMOUNTING,
MOUNT_MOUNTING_SIGTERM, MOUNT_MOUNTING_SIGKILL,
MOUNT_REMOUNTING_SIGTERM, MOUNT_REMOUNTING_SIGKILL,
MOUNT_UNMOUNTING_SIGTERM, MOUNT_UNMOUNTING_SIGKILL,
MOUNT_FAILED)) {
(void) automount_send_ready(a, a->expire_tokens, -ENODEV);
}
if (MOUNT(other)->state == MOUNT_DEAD)
(void) automount_send_ready(a, a->expire_tokens, 0);
/* The mount is in some unhappy state now, let's unfreeze any waiting clients */
if (IN_SET(MOUNT(other)->state,
MOUNT_DEAD, MOUNT_UNMOUNTING,
MOUNT_MOUNTING_SIGTERM, MOUNT_MOUNTING_SIGKILL,
MOUNT_REMOUNTING_SIGTERM, MOUNT_REMOUNTING_SIGKILL,
MOUNT_UNMOUNTING_SIGTERM, MOUNT_UNMOUNTING_SIGKILL,
MOUNT_FAILED)) {
(void) automount_send_ready(a, a->tokens, -ENODEV);
automount_set_state(a, AUTOMOUNT_WAITING);
}
}
static void automount_enter_waiting(Automount *a) {
_cleanup_close_ int ioctl_fd = -1;
int p[2] = { -1, -1 };
char name[sizeof("systemd-")-1 + DECIMAL_STR_MAX(pid_t) + 1];
char options[sizeof("fd=,pgrp=,minproto=5,maxproto=5,direct")-1
+ DECIMAL_STR_MAX(int) + DECIMAL_STR_MAX(gid_t) + 1];
bool mounted = false;
int r, dev_autofs_fd;
struct stat st;
assert(a);
assert(a->pipe_fd < 0);
assert(a->where);
set_clear(a->tokens);
r = unit_fail_if_symlink(UNIT(a), a->where);
if (r < 0)
goto fail;
(void) mkdir_p_label(a->where, 0555);
unit_warn_if_dir_nonempty(UNIT(a), a->where);
dev_autofs_fd = open_dev_autofs(UNIT(a)->manager);
if (dev_autofs_fd < 0) {
r = dev_autofs_fd;
goto fail;
}
if (pipe2(p, O_NONBLOCK|O_CLOEXEC) < 0) {
r = -errno;
goto fail;
}
xsprintf(options, "fd=%i,pgrp="PID_FMT",minproto=5,maxproto=5,direct", p[1], getpgrp());
xsprintf(name, "systemd-"PID_FMT, getpid());
if (mount(name, a->where, "autofs", 0, options) < 0) {
r = -errno;
goto fail;
}
mounted = true;
p[1] = safe_close(p[1]);
if (stat(a->where, &st) < 0) {
r = -errno;
goto fail;
}
ioctl_fd = open_ioctl_fd(dev_autofs_fd, a->where, st.st_dev);
if (ioctl_fd < 0) {
r = ioctl_fd;
goto fail;
}
r = autofs_protocol(dev_autofs_fd, ioctl_fd);
if (r < 0)
goto fail;
r = autofs_set_timeout(dev_autofs_fd, ioctl_fd, a->timeout_idle_usec);
if (r < 0)
goto fail;
/* Autofs fun fact:
*
* Unless we close the ioctl fd here, for some weird reason
* the direct mount will not receive events from the
* kernel. */
r = sd_event_add_io(UNIT(a)->manager->event, &a->pipe_event_source, p[0], EPOLLIN, automount_dispatch_io, a);
if (r < 0)
goto fail;
(void) sd_event_source_set_description(a->pipe_event_source, "automount-io");
a->pipe_fd = p[0];
a->dev_id = st.st_dev;
automount_set_state(a, AUTOMOUNT_WAITING);
return;
fail:
log_unit_error_errno(UNIT(a), r, "Failed to initialize automounter: %m");
safe_close_pair(p);
if (mounted) {
r = repeat_unmount(a->where, MNT_DETACH);
if (r < 0)
log_error_errno(r, "Failed to unmount, ignoring: %m");
}
automount_enter_dead(a, AUTOMOUNT_FAILURE_RESOURCES);
}
static void *expire_thread(void *p) {
struct autofs_dev_ioctl param;
_cleanup_(expire_data_freep) struct expire_data *data = (struct expire_data*)p;
int r;
assert(data->dev_autofs_fd >= 0);
assert(data->ioctl_fd >= 0);
init_autofs_dev_ioctl(&param);
param.ioctlfd = data->ioctl_fd;
do {
r = ioctl(data->dev_autofs_fd, AUTOFS_DEV_IOCTL_EXPIRE, &param);
} while (r >= 0);
if (errno != EAGAIN)
log_warning_errno(errno, "Failed to expire automount, ignoring: %m");
return NULL;
}
static int automount_dispatch_expire(sd_event_source *source, usec_t usec, void *userdata) {
Automount *a = AUTOMOUNT(userdata);
_cleanup_(expire_data_freep) struct expire_data *data = NULL;
int r;
assert(a);
assert(source == a->expire_event_source);
data = new0(struct expire_data, 1);
if (!data)
return log_oom();
data->ioctl_fd = -1;
data->dev_autofs_fd = fcntl(UNIT(a)->manager->dev_autofs_fd, F_DUPFD_CLOEXEC, 3);
if (data->dev_autofs_fd < 0)
return log_unit_error_errno(UNIT(a), errno, "Failed to duplicate autofs fd: %m");
data->ioctl_fd = open_ioctl_fd(UNIT(a)->manager->dev_autofs_fd, a->where, a->dev_id);
if (data->ioctl_fd < 0)
return log_unit_error_errno(UNIT(a), data->ioctl_fd, "Couldn't open autofs ioctl fd: %m");
r = asynchronous_job(expire_thread, data);
if (r < 0)
return log_unit_error_errno(UNIT(a), r, "Failed to start expire job: %m");
data = NULL;
return automount_start_expire(a);
}
static int automount_start_expire(Automount *a) {
int r;
usec_t timeout;
assert(a);
if (a->timeout_idle_usec == 0)
return 0;
timeout = now(CLOCK_MONOTONIC) + MAX(a->timeout_idle_usec/3, USEC_PER_SEC);
if (a->expire_event_source) {
r = sd_event_source_set_time(a->expire_event_source, timeout);
if (r < 0)
return r;
return sd_event_source_set_enabled(a->expire_event_source, SD_EVENT_ONESHOT);
}
r = sd_event_add_time(
UNIT(a)->manager->event,
&a->expire_event_source,
CLOCK_MONOTONIC, timeout, 0,
automount_dispatch_expire, a);
if (r < 0)
return r;
(void) sd_event_source_set_description(a->expire_event_source, "automount-expire");
return 0;
}
static void automount_stop_expire(Automount *a) {
assert(a);
if (!a->expire_event_source)
return;
(void) sd_event_source_set_enabled(a->expire_event_source, SD_EVENT_OFF);
}
static void automount_enter_runnning(Automount *a) {
_cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
struct stat st;
int r;
assert(a);
/* We don't take mount requests anymore if we are supposed to
* shut down anyway */
if (unit_stop_pending(UNIT(a))) {
log_unit_debug(UNIT(a), "Suppressing automount request since unit stop is scheduled.");
automount_send_ready(a, a->tokens, -EHOSTDOWN);
automount_send_ready(a, a->expire_tokens, -EHOSTDOWN);
return;
}
mkdir_p_label(a->where, a->directory_mode);
/* Before we do anything, let's see if somebody is playing games with us? */
if (lstat(a->where, &st) < 0) {
log_unit_warning_errno(UNIT(a), errno, "Failed to stat automount point: %m");
goto fail;
}
if (!S_ISDIR(st.st_mode) || st.st_dev != a->dev_id)
log_unit_info(UNIT(a), "Automount point already active?");
else {
Unit *trigger;
trigger = UNIT_TRIGGER(UNIT(a));
if (!trigger) {
log_unit_error(UNIT(a), "Unit to trigger vanished.");
goto fail;
}
r = manager_add_job(UNIT(a)->manager, JOB_START, trigger, JOB_REPLACE, &error, NULL);
if (r < 0) {
log_unit_warning(UNIT(a), "Failed to queue mount startup job: %s", bus_error_message(&error, r));
goto fail;
}
}
automount_set_state(a, AUTOMOUNT_RUNNING);
return;
fail:
automount_enter_dead(a, AUTOMOUNT_FAILURE_RESOURCES);
}
static int automount_start(Unit *u) {
Automount *a = AUTOMOUNT(u);
Unit *trigger;
int r;
assert(a);
assert(a->state == AUTOMOUNT_DEAD || a->state == AUTOMOUNT_FAILED);
if (path_is_mount_point(a->where, 0) > 0) {
log_unit_error(u, "Path %s is already a mount point, refusing start.", a->where);
return -EEXIST;
}
trigger = UNIT_TRIGGER(u);
if (!trigger || trigger->load_state != UNIT_LOADED) {
log_unit_error(u, "Refusing to start, unit to trigger not loaded.");
return -ENOENT;
}
r = unit_start_limit_test(u);
if (r < 0) {
automount_enter_dead(a, AUTOMOUNT_FAILURE_START_LIMIT_HIT);
return r;
}
a->result = AUTOMOUNT_SUCCESS;
automount_enter_waiting(a);
return 1;
}
static int automount_stop(Unit *u) {
Automount *a = AUTOMOUNT(u);
assert(a);
assert(a->state == AUTOMOUNT_WAITING || a->state == AUTOMOUNT_RUNNING);
automount_enter_dead(a, AUTOMOUNT_SUCCESS);
return 1;
}
static int automount_serialize(Unit *u, FILE *f, FDSet *fds) {
Automount *a = AUTOMOUNT(u);
Iterator i;
void *p;
int r;
assert(a);
assert(f);
assert(fds);
unit_serialize_item(u, f, "state", automount_state_to_string(a->state));
unit_serialize_item(u, f, "result", automount_result_to_string(a->result));
unit_serialize_item_format(u, f, "dev-id", "%u", (unsigned) a->dev_id);
SET_FOREACH(p, a->tokens, i)
unit_serialize_item_format(u, f, "token", "%u", PTR_TO_UINT(p));
SET_FOREACH(p, a->expire_tokens, i)
unit_serialize_item_format(u, f, "expire-token", "%u", PTR_TO_UINT(p));
r = unit_serialize_item_fd(u, f, fds, "pipe-fd", a->pipe_fd);
if (r < 0)
return r;
return 0;
}
static int automount_deserialize_item(Unit *u, const char *key, const char *value, FDSet *fds) {
Automount *a = AUTOMOUNT(u);
int r;
assert(a);
assert(fds);
if (streq(key, "state")) {
AutomountState state;
state = automount_state_from_string(value);
if (state < 0)
log_unit_debug(u, "Failed to parse state value: %s", value);
else
a->deserialized_state = state;
} else if (streq(key, "result")) {
AutomountResult f;
f = automount_result_from_string(value);
if (f < 0)
log_unit_debug(u, "Failed to parse result value: %s", value);
else if (f != AUTOMOUNT_SUCCESS)
a->result = f;
} else if (streq(key, "dev-id")) {
unsigned d;
if (safe_atou(value, &d) < 0)
log_unit_debug(u, "Failed to parse dev-id value: %s", value);
else
a->dev_id = (unsigned) d;
} else if (streq(key, "token")) {
unsigned token;
if (safe_atou(value, &token) < 0)
log_unit_debug(u, "Failed to parse token value: %s", value);
else {
r = set_ensure_allocated(&a->tokens, NULL);
if (r < 0) {
log_oom();
return 0;
}
r = set_put(a->tokens, UINT_TO_PTR(token));
if (r < 0)
log_unit_error_errno(u, r, "Failed to add token to set: %m");
}
} else if (streq(key, "expire-token")) {
unsigned token;
if (safe_atou(value, &token) < 0)
log_unit_debug(u, "Failed to parse token value: %s", value);
else {
r = set_ensure_allocated(&a->expire_tokens, NULL);
if (r < 0) {
log_oom();
return 0;
}
r = set_put(a->expire_tokens, UINT_TO_PTR(token));
if (r < 0)
log_unit_error_errno(u, r, "Failed to add expire token to set: %m");
}
} else if (streq(key, "pipe-fd")) {
int fd;
if (safe_atoi(value, &fd) < 0 || fd < 0 || !fdset_contains(fds, fd))
log_unit_debug(u, "Failed to parse pipe-fd value: %s", value);
else {
safe_close(a->pipe_fd);
a->pipe_fd = fdset_remove(fds, fd);
}
} else
log_unit_debug(u, "Unknown serialization key: %s", key);
return 0;
}
static UnitActiveState automount_active_state(Unit *u) {
assert(u);
return state_translation_table[AUTOMOUNT(u)->state];
}
static const char *automount_sub_state_to_string(Unit *u) {
assert(u);
return automount_state_to_string(AUTOMOUNT(u)->state);
}
static bool automount_check_gc(Unit *u) {
assert(u);
if (!UNIT_TRIGGER(u))
return false;
return UNIT_VTABLE(UNIT_TRIGGER(u))->check_gc(UNIT_TRIGGER(u));
}
static int automount_dispatch_io(sd_event_source *s, int fd, uint32_t events, void *userdata) {
_cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
union autofs_v5_packet_union packet;
Automount *a = AUTOMOUNT(userdata);
struct stat st;
Unit *trigger;
int r;
assert(a);
assert(fd == a->pipe_fd);
if (events != EPOLLIN) {
log_unit_error(UNIT(a), "Got invalid poll event %"PRIu32" on pipe (fd=%d)", events, fd);
goto fail;
}
r = loop_read_exact(a->pipe_fd, &packet, sizeof(packet), true);
if (r < 0) {
log_unit_error_errno(UNIT(a), r, "Invalid read from pipe: %m");
goto fail;
}
switch (packet.hdr.type) {
case autofs_ptype_missing_direct:
if (packet.v5_packet.pid > 0) {
_cleanup_free_ char *p = NULL;
get_process_comm(packet.v5_packet.pid, &p);
log_unit_info(UNIT(a), "Got automount request for %s, triggered by %"PRIu32" (%s)", a->where, packet.v5_packet.pid, strna(p));
} else
log_unit_debug(UNIT(a), "Got direct mount request on %s", a->where);
r = set_ensure_allocated(&a->tokens, NULL);
if (r < 0) {
log_unit_error(UNIT(a), "Failed to allocate token set.");
goto fail;
}
r = set_put(a->tokens, UINT_TO_PTR(packet.v5_packet.wait_queue_token));
if (r < 0) {
log_unit_error_errno(UNIT(a), r, "Failed to remember token: %m");
goto fail;
}
automount_enter_runnning(a);
break;
case autofs_ptype_expire_direct:
log_unit_debug(UNIT(a), "Got direct umount request on %s", a->where);
automount_stop_expire(a);
r = set_ensure_allocated(&a->expire_tokens, NULL);
if (r < 0) {
log_unit_error(UNIT(a), "Failed to allocate token set.");
goto fail;
}
r = set_put(a->expire_tokens, UINT_TO_PTR(packet.v5_packet.wait_queue_token));
if (r < 0) {
log_unit_error_errno(UNIT(a), r, "Failed to remember token: %m");
goto fail;
}
/* Before we do anything, let's see if somebody is playing games with us? */
if (lstat(a->where, &st) < 0) {
log_unit_warning_errno(UNIT(a), errno, "Failed to stat automount point: %m");
goto fail;
}
if (!S_ISDIR(st.st_mode) || st.st_dev == a->dev_id) {
log_unit_info(UNIT(a), "Automount point already unmounted?");
automount_send_ready(a, a->expire_tokens, 0);
break;
}
trigger = UNIT_TRIGGER(UNIT(a));
if (!trigger) {
log_unit_error(UNIT(a), "Unit to trigger vanished.");
goto fail;
}
r = manager_add_job(UNIT(a)->manager, JOB_STOP, trigger, JOB_REPLACE, &error, NULL);
if (r < 0) {
log_unit_warning(UNIT(a), "Failed to queue umount startup job: %s", bus_error_message(&error, r));
goto fail;
}
break;
default:
log_unit_error(UNIT(a), "Received unknown automount request %i", packet.hdr.type);
break;
}
return 0;
fail:
automount_enter_dead(a, AUTOMOUNT_FAILURE_RESOURCES);
return 0;
}
static void automount_shutdown(Manager *m) {
assert(m);
m->dev_autofs_fd = safe_close(m->dev_autofs_fd);
}
static void automount_reset_failed(Unit *u) {
Automount *a = AUTOMOUNT(u);
assert(a);
if (a->state == AUTOMOUNT_FAILED)
automount_set_state(a, AUTOMOUNT_DEAD);
a->result = AUTOMOUNT_SUCCESS;
}
static bool automount_supported(void) {
static int supported = -1;
if (supported < 0)
supported = access("/dev/autofs", F_OK) >= 0;
return supported;
}
static const char* const automount_result_table[_AUTOMOUNT_RESULT_MAX] = {
[AUTOMOUNT_SUCCESS] = "success",
[AUTOMOUNT_FAILURE_RESOURCES] = "resources",
[AUTOMOUNT_FAILURE_START_LIMIT_HIT] = "start-limit-hit",
[AUTOMOUNT_FAILURE_MOUNT_START_LIMIT_HIT] = "mount-start-limit-hit",
};
DEFINE_STRING_TABLE_LOOKUP(automount_result, AutomountResult);
const UnitVTable automount_vtable = {
.object_size = sizeof(Automount),
.sections =
"Unit\0"
"Automount\0"
"Install\0",
.init = automount_init,
.load = automount_load,
.done = automount_done,
.coldplug = automount_coldplug,
.dump = automount_dump,
.start = automount_start,
.stop = automount_stop,
.serialize = automount_serialize,
.deserialize_item = automount_deserialize_item,
.active_state = automount_active_state,
.sub_state_to_string = automount_sub_state_to_string,
.check_gc = automount_check_gc,
.trigger_notify = automount_trigger_notify,
.reset_failed = automount_reset_failed,
.bus_vtable = bus_automount_vtable,
.shutdown = automount_shutdown,
.supported = automount_supported,
.status_message_formats = {
.finished_start_job = {
[JOB_DONE] = "Set up automount %s.",
[JOB_FAILED] = "Failed to set up automount %s.",
},
.finished_stop_job = {
[JOB_DONE] = "Unset automount %s.",
[JOB_FAILED] = "Failed to unset automount %s.",
},
},
};
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