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udevd.c
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udevd.c
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/* SPDX-License-Identifier: GPL-2.0+ */
/*
* Copyright © 2004 Chris Friesen <chris_friesen@sympatico.ca>
* Copyright © 2009 Canonical Ltd.
* Copyright © 2009 Scott James Remnant <scott@netsplit.com>
*/
#include <errno.h>
#include <fcntl.h>
#include <getopt.h>
#include <stdbool.h>
#include <stddef.h>
#include <stdio.h>
#include <stdlib.h>
#include <sys/epoll.h>
#include <sys/file.h>
#include <sys/inotify.h>
#include <sys/ioctl.h>
#include <sys/mount.h>
#include <sys/prctl.h>
#include <sys/signalfd.h>
#include <sys/stat.h>
#include <sys/time.h>
#include <sys/wait.h>
#include <unistd.h>
#include "sd-daemon.h"
#include "sd-event.h"
#include "alloc-util.h"
#include "build.h"
#include "cgroup-util.h"
#include "cpu-set-util.h"
#include "dev-setup.h"
#include "device-monitor-private.h"
#include "device-private.h"
#include "device-util.h"
#include "event-util.h"
#include "fd-util.h"
#include "fileio.h"
#include "format-util.h"
#include "fs-util.h"
#include "hashmap.h"
#include "io-util.h"
#include "libudev-device-internal.h"
#include "limits-util.h"
#include "list.h"
#include "main-func.h"
#include "mkdir.h"
#include "netlink-util.h"
#include "parse-util.h"
#include "pretty-print.h"
#include "proc-cmdline.h"
#include "process-util.h"
#include "selinux-util.h"
#include "signal-util.h"
#include "socket-util.h"
#include "string-util.h"
#include "strv.h"
#include "strxcpyx.h"
#include "syslog-util.h"
#include "udev-builtin.h"
#include "udev-ctrl.h"
#include "udev-event.h"
#include "udev-util.h"
#include "udev-watch.h"
#include "user-util.h"
#define WORKER_NUM_MAX 2048U
static bool arg_debug = false;
static int arg_daemonize = false;
static ResolveNameTiming arg_resolve_name_timing = RESOLVE_NAME_EARLY;
static unsigned arg_children_max = 0;
static usec_t arg_exec_delay_usec = 0;
static usec_t arg_event_timeout_usec = 180 * USEC_PER_SEC;
typedef struct Manager {
sd_event *event;
Hashmap *workers;
LIST_HEAD(struct event, events);
const char *cgroup;
pid_t pid; /* the process that originally allocated the manager object */
UdevRules *rules;
Hashmap *properties;
sd_netlink *rtnl;
sd_device_monitor *monitor;
struct udev_ctrl *ctrl;
int fd_inotify;
int worker_watch[2];
sd_event_source *inotify_event;
sd_event_source *kill_workers_event;
usec_t last_usec;
bool stop_exec_queue:1;
bool exit:1;
} Manager;
enum event_state {
EVENT_UNDEF,
EVENT_QUEUED,
EVENT_RUNNING,
};
struct event {
Manager *manager;
struct worker *worker;
enum event_state state;
sd_device *dev;
sd_device *dev_kernel; /* clone of originally received device */
uint64_t seqnum;
uint64_t delaying_seqnum;
sd_event_source *timeout_warning_event;
sd_event_source *timeout_event;
LIST_FIELDS(struct event, event);
};
static void event_queue_cleanup(Manager *manager, enum event_state type);
enum worker_state {
WORKER_UNDEF,
WORKER_RUNNING,
WORKER_IDLE,
WORKER_KILLED,
};
struct worker {
Manager *manager;
pid_t pid;
sd_device_monitor *monitor;
enum worker_state state;
struct event *event;
};
/* passed from worker to main process */
struct worker_message {
};
static void event_free(struct event *event) {
if (!event)
return;
assert(event->manager);
LIST_REMOVE(event, event->manager->events, event);
sd_device_unref(event->dev);
sd_device_unref(event->dev_kernel);
sd_event_source_unref(event->timeout_warning_event);
sd_event_source_unref(event->timeout_event);
if (event->worker)
event->worker->event = NULL;
/* only clean up the queue from the process that created it */
if (LIST_IS_EMPTY(event->manager->events) &&
event->manager->pid == getpid_cached())
if (unlink("/run/udev/queue") < 0)
log_warning_errno(errno, "Failed to unlink /run/udev/queue: %m");
free(event);
}
static void worker_free(struct worker *worker) {
if (!worker)
return;
assert(worker->manager);
hashmap_remove(worker->manager->workers, PID_TO_PTR(worker->pid));
sd_device_monitor_unref(worker->monitor);
event_free(worker->event);
free(worker);
}
DEFINE_TRIVIAL_CLEANUP_FUNC(struct worker *, worker_free);
DEFINE_PRIVATE_HASH_OPS_WITH_VALUE_DESTRUCTOR(worker_hash_op, void, trivial_hash_func, trivial_compare_func, struct worker, worker_free);
static int worker_new(struct worker **ret, Manager *manager, sd_device_monitor *worker_monitor, pid_t pid) {
_cleanup_(worker_freep) struct worker *worker = NULL;
int r;
assert(ret);
assert(manager);
assert(worker_monitor);
assert(pid > 1);
/* close monitor, but keep address around */
device_monitor_disconnect(worker_monitor);
worker = new(struct worker, 1);
if (!worker)
return -ENOMEM;
*worker = (struct worker) {
.manager = manager,
.monitor = sd_device_monitor_ref(worker_monitor),
.pid = pid,
};
r = hashmap_ensure_allocated(&manager->workers, &worker_hash_op);
if (r < 0)
return r;
r = hashmap_put(manager->workers, PID_TO_PTR(pid), worker);
if (r < 0)
return r;
*ret = TAKE_PTR(worker);
return 0;
}
static int on_event_timeout(sd_event_source *s, uint64_t usec, void *userdata) {
struct event *event = userdata;
assert(event);
assert(event->worker);
kill_and_sigcont(event->worker->pid, SIGKILL);
event->worker->state = WORKER_KILLED;
log_device_error(event->dev, "Worker ["PID_FMT"] processing SEQNUM=%"PRIu64" killed", event->worker->pid, event->seqnum);
return 1;
}
static int on_event_timeout_warning(sd_event_source *s, uint64_t usec, void *userdata) {
struct event *event = userdata;
assert(event);
assert(event->worker);
log_device_warning(event->dev, "Worker ["PID_FMT"] processing SEQNUM=%"PRIu64" is taking a long time", event->worker->pid, event->seqnum);
return 1;
}
static void worker_attach_event(struct worker *worker, struct event *event) {
sd_event *e;
uint64_t usec;
assert(worker);
assert(worker->manager);
assert(event);
assert(!event->worker);
assert(!worker->event);
worker->state = WORKER_RUNNING;
worker->event = event;
event->state = EVENT_RUNNING;
event->worker = worker;
e = worker->manager->event;
assert_se(sd_event_now(e, CLOCK_MONOTONIC, &usec) >= 0);
(void) sd_event_add_time(e, &event->timeout_warning_event, CLOCK_MONOTONIC,
usec + udev_warn_timeout(arg_event_timeout_usec), USEC_PER_SEC, on_event_timeout_warning, event);
(void) sd_event_add_time(e, &event->timeout_event, CLOCK_MONOTONIC,
usec + arg_event_timeout_usec, USEC_PER_SEC, on_event_timeout, event);
}
static void manager_clear_for_worker(Manager *manager) {
assert(manager);
manager->inotify_event = sd_event_source_unref(manager->inotify_event);
manager->kill_workers_event = sd_event_source_unref(manager->kill_workers_event);
manager->event = sd_event_unref(manager->event);
manager->workers = hashmap_free(manager->workers);
event_queue_cleanup(manager, EVENT_UNDEF);
manager->monitor = sd_device_monitor_unref(manager->monitor);
manager->ctrl = udev_ctrl_unref(manager->ctrl);
manager->worker_watch[READ_END] = safe_close(manager->worker_watch[READ_END]);
}
static void manager_free(Manager *manager) {
if (!manager)
return;
udev_builtin_exit();
if (manager->pid == getpid_cached())
udev_ctrl_cleanup(manager->ctrl);
manager_clear_for_worker(manager);
sd_netlink_unref(manager->rtnl);
hashmap_free_free_free(manager->properties);
udev_rules_free(manager->rules);
safe_close(manager->fd_inotify);
safe_close_pair(manager->worker_watch);
free(manager);
}
DEFINE_TRIVIAL_CLEANUP_FUNC(Manager*, manager_free);
static int worker_send_message(int fd) {
struct worker_message message = {};
return loop_write(fd, &message, sizeof(message), false);
}
static int worker_lock_and_watch_block_device(sd_device *dev, int *ret_fd, int *watch_fd) {
_cleanup_close_ int fd = -1;
_cleanup_close_ int ifd = -1;
const char *val;
int r;
assert(dev);
assert(ret_fd);
assert(watch_fd);
/*
* Take a shared lock on the device node; this establishes
* a concept of device "ownership" to serialize device
* access. External processes holding an exclusive lock will
* cause udev to skip the event handling; in the case udev
* acquired the lock, the external process can block until
* udev has finished its event handling.
*/
if (device_for_action(dev, DEVICE_ACTION_REMOVE))
return 0;
r = sd_device_get_subsystem(dev, &val);
if (r < 0)
return log_device_debug_errno(dev, r, "Failed to get subsystem: %m");
if (!streq(val, "block"))
return 0;
r = sd_device_get_sysname(dev, &val);
if (r < 0)
return log_device_debug_errno(dev, r, "Failed to get sysname: %m");
if (STARTSWITH_SET(val, "dm-", "md", "drbd"))
return 0;
r = sd_device_get_devtype(dev, &val);
if (r < 0 && r != -ENOENT)
return log_device_debug_errno(dev, r, "Failed to get devtype: %m");
if (r >= 0 && streq(val, "partition")) {
r = sd_device_get_parent(dev, &dev);
if (r < 0)
return log_device_debug_errno(dev, r, "Failed to get parent device: %m");
}
r = sd_device_get_devname(dev, &val);
if (r == -ENOENT)
return 0;
if (r < 0)
return log_device_debug_errno(dev, r, "Failed to get devname: %m");
fd = open(val, O_RDONLY|O_CLOEXEC|O_NOFOLLOW|O_NONBLOCK);
if (fd < 0) {
log_device_debug_errno(dev, errno, "Failed to open '%s', ignoring: %m", val);
return 0;
}
if (flock(fd, LOCK_SH|LOCK_NB) < 0)
return log_device_debug_errno(dev, errno, "Failed to flock(%s): %m", val);
ifd = inotify_init1(IN_NONBLOCK|IN_CLOEXEC);
if (ifd < 0)
return log_device_debug_errno(dev, errno, "Failed to inotify_init: %m");
if (inotify_add_watch(ifd, val, IN_CLOSE_WRITE) < 0)
return log_device_debug_errno(dev, errno, "Failed to inotify_add_watch(%s): %m", val);
*ret_fd = TAKE_FD(fd);
*watch_fd = TAKE_FD(ifd);
return 1;
}
static int worker_process_device(Manager *manager, sd_device *dev) {
_cleanup_(udev_event_freep) UdevEvent *udev_event = NULL;
_cleanup_close_ int fd_lock = -1;
_cleanup_close_ int fd_watch = -1;
DeviceAction action;
uint64_t seqnum;
int r;
assert(manager);
assert(dev);
r = device_get_seqnum(dev, &seqnum);
if (r < 0)
return log_device_debug_errno(dev, r, "Failed to get SEQNUM: %m");
r = device_get_action(dev, &action);
if (r < 0)
return log_device_debug_errno(dev, r, "Failed to get ACTION: %m");
log_device_debug(dev, "Processing device (SEQNUM=%"PRIu64", ACTION=%s)",
seqnum, device_action_to_string(action));
udev_event = udev_event_new(dev, arg_exec_delay_usec, manager->rtnl);
if (!udev_event)
return -ENOMEM;
/* We take a shared flock on any block devices, so any external program that modifies the block
* device race with us while we're processing it, below, if the external program takes an
* exclusive flock on the block device. However, any external program that modifies the block
* device *without* taking an exclusive flock can still race with us, and we may miss an update
* of the block device (leading to missing /dev/disk symlinks, etc). So we also set a inotify
* watch that we check after processing.
*
* Note that we can't use the real watch this early, because 1) udev_event_execute_rules removes
* the watch and 2) we don't know if we should start the real watch yet, as ->inotify_watch is
* set during udev_event_execute_rules.
*/
r = worker_lock_and_watch_block_device(dev, &fd_lock, &watch_lock);
if (r < 0)
return r;
/* apply rules, create node, symlinks */
r = udev_event_execute_rules(udev_event, arg_event_timeout_usec, manager->properties, manager->rules);
if (r < 0)
return r;
udev_event_execute_run(udev_event, arg_event_timeout_usec);
if (!manager->rtnl)
/* in case rtnl was initialized */
manager->rtnl = sd_netlink_ref(udev_event->rtnl);
/* apply/restore inotify watch */
if (udev_event->inotify_watch) {
(void) udev_watch_begin(dev);
r = device_update_db(dev);
if (r < 0)
return log_device_debug_errno(dev, r, "Failed to update database under /run/udev/data/: %m");
}
log_device_debug(dev, "Device (SEQNUM=%"PRIu64", ACTION=%s) processed",
seqnum, device_action_to_string(action));
/* We've processed the block device now, and we started the real watch, so we just
* need to check if there was any IN_CLOSE_WRITE that we missed while processing,
* before the real watch was started.
*/
if (watch_fd >=0) {
union inotify_event_buffer buffer;
struct inotify_event *e;
bool change = false;
while (!change) {
r = read(watch_fd, &buffer, sizeof(buffer));
if (r < 0)
break;
FOREACH_INOTIFY_EVENT(e, buffer, r)
if (e->mask & IN_CLOSE_WRITE) {
change = true;
break;
}
}
if (change)
synthesize_change(dev);
}
return 0;
}
static int worker_device_monitor_handler(sd_device_monitor *monitor, sd_device *dev, void *userdata) {
Manager *manager = userdata;
int r;
assert(dev);
assert(manager);
r = worker_process_device(manager, dev);
if (r < 0)
log_device_warning_errno(dev, r, "Failed to process device, ignoring: %m");
/* send processed event back to libudev listeners */
r = device_monitor_send_device(monitor, NULL, dev);
if (r < 0)
log_device_warning_errno(dev, r, "Failed to send device, ignoring: %m");
/* send udevd the result of the event execution */
r = worker_send_message(manager->worker_watch[WRITE_END]);
if (r < 0)
log_device_warning_errno(dev, r, "Failed to send signal to main daemon, ignoring: %m");
return 1;
}
static int worker_main(Manager *_manager, sd_device_monitor *monitor, sd_device *first_device) {
_cleanup_(sd_device_unrefp) sd_device *dev = first_device;
_cleanup_(manager_freep) Manager *manager = _manager;
int r;
assert(manager);
assert(monitor);
assert(dev);
unsetenv("NOTIFY_SOCKET");
assert_se(sigprocmask_many(SIG_BLOCK, NULL, SIGTERM, -1) >= 0);
/* Reset OOM score, we only protect the main daemon. */
r = set_oom_score_adjust(0);
if (r < 0)
log_debug_errno(r, "Failed to reset OOM score, ignoring: %m");
/* Clear unnecessary data in Manager object.*/
manager_clear_for_worker(manager);
r = sd_event_new(&manager->event);
if (r < 0)
return log_error_errno(r, "Failed to allocate event loop: %m");
r = sd_event_add_signal(manager->event, NULL, SIGTERM, NULL, NULL);
if (r < 0)
return log_error_errno(r, "Failed to set SIGTERM event: %m");
r = sd_device_monitor_attach_event(monitor, manager->event);
if (r < 0)
return log_error_errno(r, "Failed to attach event loop to device monitor: %m");
r = sd_device_monitor_start(monitor, worker_device_monitor_handler, manager);
if (r < 0)
return log_error_errno(r, "Failed to start device monitor: %m");
(void) sd_event_source_set_description(sd_device_monitor_get_event_source(monitor), "worker-device-monitor");
/* Process first device */
(void) worker_device_monitor_handler(monitor, dev, manager);
r = sd_event_loop(manager->event);
if (r < 0)
return log_error_errno(r, "Event loop failed: %m");
return 0;
}
static int worker_spawn(Manager *manager, struct event *event) {
_cleanup_(sd_device_monitor_unrefp) sd_device_monitor *worker_monitor = NULL;
struct worker *worker;
pid_t pid;
int r;
/* listen for new events */
r = device_monitor_new_full(&worker_monitor, MONITOR_GROUP_NONE, -1);
if (r < 0)
return r;
/* allow the main daemon netlink address to send devices to the worker */
r = device_monitor_allow_unicast_sender(worker_monitor, manager->monitor);
if (r < 0)
return log_error_errno(r, "Worker: Failed to set unicast sender: %m");
r = device_monitor_enable_receiving(worker_monitor);
if (r < 0)
return log_error_errno(r, "Worker: Failed to enable receiving of device: %m");
r = safe_fork(NULL, FORK_DEATHSIG, &pid);
if (r < 0) {
event->state = EVENT_QUEUED;
return log_error_errno(r, "Failed to fork() worker: %m");
}
if (r == 0) {
/* Worker process */
r = worker_main(manager, worker_monitor, sd_device_ref(event->dev));
log_close();
_exit(r < 0 ? EXIT_FAILURE : EXIT_SUCCESS);
}
r = worker_new(&worker, manager, worker_monitor, pid);
if (r < 0)
return log_error_errno(r, "Failed to create worker object: %m");
worker_attach_event(worker, event);
log_device_debug(event->dev, "Worker ["PID_FMT"] is forked for processing SEQNUM=%"PRIu64".", pid, event->seqnum);
return 0;
}
static void event_run(Manager *manager, struct event *event) {
static bool log_children_max_reached = true;
struct worker *worker;
Iterator i;
int r;
assert(manager);
assert(event);
if (DEBUG_LOGGING) {
DeviceAction action;
r = device_get_action(event->dev, &action);
log_device_debug(event->dev, "Device (SEQNUM=%"PRIu64", ACTION=%s) ready for processing",
event->seqnum, r >= 0 ? device_action_to_string(action) : "<unknown>");
}
HASHMAP_FOREACH(worker, manager->workers, i) {
if (worker->state != WORKER_IDLE)
continue;
r = device_monitor_send_device(manager->monitor, worker->monitor, event->dev);
if (r < 0) {
log_device_error_errno(event->dev, r, "Worker ["PID_FMT"] did not accept message, killing the worker: %m",
worker->pid);
(void) kill(worker->pid, SIGKILL);
worker->state = WORKER_KILLED;
continue;
}
worker_attach_event(worker, event);
return;
}
if (hashmap_size(manager->workers) >= arg_children_max) {
/* Avoid spamming the debug logs if the limit is already reached and
* many events still need to be processed */
if (log_children_max_reached && arg_children_max > 1) {
log_debug("Maximum number (%u) of children reached.", hashmap_size(manager->workers));
log_children_max_reached = false;
}
return;
}
/* Re-enable the debug message for the next batch of events */
log_children_max_reached = true;
/* start new worker and pass initial device */
worker_spawn(manager, event);
}
static int event_queue_insert(Manager *manager, sd_device *dev) {
_cleanup_(sd_device_unrefp) sd_device *clone = NULL;
struct event *event;
DeviceAction action;
uint64_t seqnum;
int r;
assert(manager);
assert(dev);
/* only one process can add events to the queue */
assert(manager->pid == getpid_cached());
/* We only accepts devices received by device monitor. */
r = device_get_seqnum(dev, &seqnum);
if (r < 0)
return r;
/* Refuse devices do not have ACTION property. */
r = device_get_action(dev, &action);
if (r < 0)
return r;
/* Save original device to restore the state on failures. */
r = device_shallow_clone(dev, &clone);
if (r < 0)
return r;
r = device_copy_properties(clone, dev);
if (r < 0)
return r;
event = new(struct event, 1);
if (!event)
return -ENOMEM;
*event = (struct event) {
.manager = manager,
.dev = sd_device_ref(dev),
.dev_kernel = TAKE_PTR(clone),
.seqnum = seqnum,
.state = EVENT_QUEUED,
};
if (LIST_IS_EMPTY(manager->events)) {
r = touch("/run/udev/queue");
if (r < 0)
log_warning_errno(r, "Failed to touch /run/udev/queue: %m");
}
LIST_APPEND(event, manager->events, event);
log_device_debug(dev, "Device (SEQNUM=%"PRIu64", ACTION=%s) is queued",
seqnum, device_action_to_string(action));
return 0;
}
static void manager_kill_workers(Manager *manager) {
struct worker *worker;
Iterator i;
assert(manager);
HASHMAP_FOREACH(worker, manager->workers, i) {
if (worker->state == WORKER_KILLED)
continue;
worker->state = WORKER_KILLED;
(void) kill(worker->pid, SIGTERM);
}
}
/* lookup event for identical, parent, child device */
static int is_device_busy(Manager *manager, struct event *event) {
const char *subsystem, *devpath, *devpath_old = NULL;
dev_t devnum = makedev(0, 0);
struct event *loop_event;
size_t devpath_len;
int r, ifindex = 0;
bool is_block;
r = sd_device_get_subsystem(event->dev, &subsystem);
if (r < 0)
return r;
is_block = streq(subsystem, "block");
r = sd_device_get_devpath(event->dev, &devpath);
if (r < 0)
return r;
devpath_len = strlen(devpath);
r = sd_device_get_property_value(event->dev, "DEVPATH_OLD", &devpath_old);
if (r < 0 && r != -ENOENT)
return r;
r = sd_device_get_devnum(event->dev, &devnum);
if (r < 0 && r != -ENOENT)
return r;
r = sd_device_get_ifindex(event->dev, &ifindex);
if (r < 0 && r != -ENOENT)
return r;
/* check if queue contains events we depend on */
LIST_FOREACH(event, loop_event, manager->events) {
size_t loop_devpath_len, common;
const char *loop_devpath;
/* we already found a later event, earlier cannot block us, no need to check again */
if (loop_event->seqnum < event->delaying_seqnum)
continue;
/* event we checked earlier still exists, no need to check again */
if (loop_event->seqnum == event->delaying_seqnum)
return true;
/* found ourself, no later event can block us */
if (loop_event->seqnum >= event->seqnum)
break;
/* check major/minor */
if (major(devnum) != 0) {
const char *s;
dev_t d;
if (sd_device_get_subsystem(loop_event->dev, &s) < 0)
continue;
if (sd_device_get_devnum(loop_event->dev, &d) >= 0 &&
devnum == d && is_block == streq(s, "block"))
goto set_delaying_seqnum;
}
/* check network device ifindex */
if (ifindex > 0) {
int i;
if (sd_device_get_ifindex(loop_event->dev, &i) >= 0 &&
ifindex == i)
goto set_delaying_seqnum;
}
if (sd_device_get_devpath(loop_event->dev, &loop_devpath) < 0)
continue;
/* check our old name */
if (devpath_old && streq(devpath_old, loop_devpath))
goto set_delaying_seqnum;
loop_devpath_len = strlen(loop_devpath);
/* compare devpath */
common = MIN(devpath_len, loop_devpath_len);
/* one devpath is contained in the other? */
if (!strneq(devpath, loop_devpath, common))
continue;
/* identical device event found */
if (devpath_len == loop_devpath_len)
goto set_delaying_seqnum;
/* parent device event found */
if (devpath[common] == '/')
goto set_delaying_seqnum;
/* child device event found */
if (loop_devpath[common] == '/')
goto set_delaying_seqnum;
}
return false;
set_delaying_seqnum:
log_device_debug(event->dev, "SEQNUM=%" PRIu64 " blocked by SEQNUM=%" PRIu64,
event->seqnum, loop_event->seqnum);
event->delaying_seqnum = loop_event->seqnum;
return true;
}
static void manager_exit(Manager *manager) {
assert(manager);
manager->exit = true;
sd_notify(false,
"STOPPING=1\n"
"STATUS=Starting shutdown...");
/* close sources of new events and discard buffered events */
manager->ctrl = udev_ctrl_unref(manager->ctrl);
manager->inotify_event = sd_event_source_unref(manager->inotify_event);
manager->fd_inotify = safe_close(manager->fd_inotify);
manager->monitor = sd_device_monitor_unref(manager->monitor);
/* discard queued events and kill workers */
event_queue_cleanup(manager, EVENT_QUEUED);
manager_kill_workers(manager);
}
/* reload requested, HUP signal received, rules changed, builtin changed */
static void manager_reload(Manager *manager) {
assert(manager);
sd_notify(false,
"RELOADING=1\n"
"STATUS=Flushing configuration...");
manager_kill_workers(manager);
manager->rules = udev_rules_free(manager->rules);
udev_builtin_exit();
sd_notifyf(false,
"READY=1\n"
"STATUS=Processing with %u children at max", arg_children_max);
}
static int on_kill_workers_event(sd_event_source *s, uint64_t usec, void *userdata) {
Manager *manager = userdata;
assert(manager);
log_debug("Cleanup idle workers");
manager_kill_workers(manager);
return 1;
}
static void event_queue_start(Manager *manager) {
struct event *event;
usec_t usec;
int r;
assert(manager);
if (LIST_IS_EMPTY(manager->events) ||
manager->exit || manager->stop_exec_queue)
return;
assert_se(sd_event_now(manager->event, CLOCK_MONOTONIC, &usec) >= 0);
/* check for changed config, every 3 seconds at most */
if (manager->last_usec == 0 ||
usec - manager->last_usec > 3 * USEC_PER_SEC) {
if (udev_rules_check_timestamp(manager->rules) ||
udev_builtin_validate())
manager_reload(manager);
manager->last_usec = usec;
}
r = event_source_disable(manager->kill_workers_event);
if (r < 0)
log_warning_errno(r, "Failed to disable event source for cleaning up idle workers, ignoring: %m");
udev_builtin_init();
if (!manager->rules) {
r = udev_rules_new(&manager->rules, arg_resolve_name_timing);
if (r < 0) {
log_warning_errno(r, "Failed to read udev rules: %m");
return;
}
}
LIST_FOREACH(event, event, manager->events) {
if (event->state != EVENT_QUEUED)
continue;
/* do not start event if parent or child event is still running */
if (is_device_busy(manager, event) != 0)
continue;
event_run(manager, event);
}
}
static void event_queue_cleanup(Manager *manager, enum event_state match_type) {
struct event *event, *tmp;
LIST_FOREACH_SAFE(event, event, tmp, manager->events) {
if (match_type != EVENT_UNDEF && match_type != event->state)
continue;
event_free(event);
}
}
static int on_worker(sd_event_source *s, int fd, uint32_t revents, void *userdata) {
Manager *manager = userdata;
assert(manager);
for (;;) {
struct worker_message msg;
struct iovec iovec = {
.iov_base = &msg,
.iov_len = sizeof(msg),
};
union {
struct cmsghdr cmsghdr;
uint8_t buf[CMSG_SPACE(sizeof(struct ucred))];
} control = {};
struct msghdr msghdr = {
.msg_iov = &iovec,
.msg_iovlen = 1,
.msg_control = &control,
.msg_controllen = sizeof(control),
};
ssize_t size;
struct ucred *ucred;
struct worker *worker;
size = recvmsg_safe(fd, &msghdr, MSG_DONTWAIT);
if (size == -EINTR)
continue;
if (size == -EAGAIN)
/* nothing more to read */
break;
if (size < 0)
return log_error_errno(size, "Failed to receive message: %m");
cmsg_close_all(&msghdr);
if (size != sizeof(struct worker_message)) {
log_warning("Ignoring worker message with invalid size %zi bytes", size);
continue;
}
ucred = CMSG_FIND_DATA(&msghdr, SOL_SOCKET, SCM_CREDENTIALS, struct ucred);
if (!ucred || ucred->pid <= 0) {
log_warning("Ignoring worker message without valid PID");
continue;
}
/* lookup worker who sent the signal */
worker = hashmap_get(manager->workers, PID_TO_PTR(ucred->pid));
if (!worker) {
log_debug("Worker ["PID_FMT"] returned, but is no longer tracked", ucred->pid);
continue;
}
if (worker->state != WORKER_KILLED)
worker->state = WORKER_IDLE;