X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=udev%2Fudevd.c;h=e7a0c9840aba4b23e71b0e36877c78bcf3bbdb6b;hp=50205f1e43c3e4ddee4f3049bab5c9ede42510a1;hb=45798927f8532cd412622e9762619b46a9b638cd;hpb=521b3a9211b4e2d98bf7ae61c3844a42dde773e2 diff --git a/udev/udevd.c b/udev/udevd.c index 50205f1e4..e7a0c9840 100644 --- a/udev/udevd.c +++ b/udev/udevd.c @@ -1,6 +1,8 @@ /* - * Copyright (C) 2004-2008 Kay Sievers + * Copyright (C) 2004-2009 Kay Sievers * Copyright (C) 2004 Chris Friesen + * Copyright (C) 2009 Canonical Ltd. + * Copyright (C) 2009 Scott James Remnant * * This program is free software: you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by @@ -28,23 +30,21 @@ #include #include #include +#include +#include +#include #include #include #include #include #include -#ifdef HAVE_INOTIFY #include -#endif #include "udev.h" #define UDEVD_PRIORITY -4 #define UDEV_PRIORITY -2 -/* maximum limit of forked childs */ -#define UDEVD_MAX_CHILDS 256 - static int debug; static void log_fn(struct udev *udev, int priority, @@ -59,244 +59,348 @@ static void log_fn(struct udev *udev, int priority, } } -static void reap_sigchilds(void); - static int debug_trace; static struct udev_rules *rules; +static struct udev_queue_export *udev_queue_export; static struct udev_ctrl *udev_ctrl; -static struct udev_monitor *kernel_monitor; -static volatile int sigchilds_waiting; -static volatile int udev_exit; -static volatile int reload_config; -static volatile int signal_received; -static int run_exec_q; -static int stop_exec_q; +static struct udev_monitor *monitor; +static int worker_watch[2]; +static pid_t settle_pid; +static int stop_exec_queue; +static int reload_config; static int max_childs; static int childs; static struct udev_list_node event_list; +static struct udev_list_node worker_list; +static int udev_exit; +static volatile sig_atomic_t worker_exit; + +enum poll_fd { + FD_CONTROL, + FD_NETLINK, + FD_INOTIFY, + FD_SIGNAL, + FD_WORKER, +}; + +static struct pollfd pfd[] = { + [FD_NETLINK] = { .events = POLLIN }, + [FD_WORKER] = { .events = POLLIN }, + [FD_SIGNAL] = { .events = POLLIN }, + [FD_INOTIFY] = { .events = POLLIN }, + [FD_CONTROL] = { .events = POLLIN }, +}; enum event_state { + EVENT_UNDEF, EVENT_QUEUED, - EVENT_FINISHED, - EVENT_FAILED, + EVENT_RUNNING, +}; + +struct event { + struct udev_list_node node; + struct udev *udev; + struct udev_device *dev; + enum event_state state; + int exitcode; + unsigned long long int delaying_seqnum; + unsigned long long int seqnum; + const char *devpath; + size_t devpath_len; + const char *devpath_old; }; -static struct udev_event *node_to_event(struct udev_list_node *node) +static struct event *node_to_event(struct udev_list_node *node) { char *event; event = (char *)node; - event -= offsetof(struct udev_event, node); - return (struct udev_event *)event; + event -= offsetof(struct event, node); + return (struct event *)event; } -static void export_event_state(struct udev_event *event, enum event_state state) -{ - char filename[UTIL_PATH_SIZE]; - char filename_failed[UTIL_PATH_SIZE]; - size_t start; - - /* location of queue file */ - snprintf(filename, sizeof(filename), "%s/.udev/queue/%llu", - udev_get_dev_path(event->udev), udev_device_get_seqnum(event->dev)); - - /* location of failed file */ - util_strlcpy(filename_failed, udev_get_dev_path(event->udev), sizeof(filename_failed)); - util_strlcat(filename_failed, "/", sizeof(filename_failed)); - start = util_strlcat(filename_failed, ".udev/failed/", sizeof(filename_failed)); - util_strlcat(filename_failed, udev_device_get_devpath(event->dev), sizeof(filename_failed)); - util_path_encode(&filename_failed[start], sizeof(filename_failed) - start); - - switch (state) { - case EVENT_QUEUED: - if(unlink(filename_failed) == 0) - util_delete_path(event->udev, filename_failed); - util_create_path(event->udev, filename); - udev_selinux_setfscreatecon(event->udev, filename, S_IFLNK); - symlink(udev_device_get_devpath(event->dev), filename); - udev_selinux_resetfscreatecon(event->udev); - break; - case EVENT_FINISHED: - if (udev_device_get_devpath_old(event->dev) != NULL) { - /* "move" event - rename failed file to current name, do not delete failed */ - char filename_failed_old[UTIL_PATH_SIZE]; - - util_strlcpy(filename_failed_old, udev_get_dev_path(event->udev), sizeof(filename_failed_old)); - util_strlcat(filename_failed_old, "/", sizeof(filename_failed_old)); - start = util_strlcat(filename_failed_old, ".udev/failed/", sizeof(filename_failed_old)); - util_strlcat(filename_failed_old, udev_device_get_devpath_old(event->dev), sizeof(filename_failed_old)); - util_path_encode(&filename_failed_old[start], sizeof(filename) - start); - - if (rename(filename_failed_old, filename_failed) == 0) - info(event->udev, "renamed devpath, moved failed state of '%s' to %s'\n", - udev_device_get_devpath_old(event->dev), udev_device_get_devpath(event->dev)); - } else { - if (unlink(filename_failed) == 0) - util_delete_path(event->udev, filename_failed); - } +enum worker_state { + WORKER_UNDEF, + WORKER_RUNNING, + WORKER_IDLE, + WORKER_KILLED, +}; + +struct worker { + struct udev_list_node node; + pid_t pid; + struct udev_monitor *monitor; + enum worker_state state; + struct event *event; +}; - unlink(filename); +/* passed from worker to main process */ +struct worker_message { + pid_t pid; + int exitcode; +}; - /* clean up possibly empty queue directory */ - if (udev_list_is_empty(&event_list)) - util_delete_path(event->udev, filename); - break; - case EVENT_FAILED: - /* move failed event to the failed directory */ - util_create_path(event->udev, filename_failed); - rename(filename, filename_failed); - - /* clean up possibly empty queue directory */ - if (udev_list_is_empty(&event_list)) - util_delete_path(event->udev, filename); - break; - } +static struct worker *node_to_worker(struct udev_list_node *node) +{ + char *worker; - return; + worker = (char *)node; + worker -= offsetof(struct worker, node); + return (struct worker *)worker; } -static void event_queue_delete(struct udev_event *event) +static void event_queue_delete(struct event *event) { udev_list_node_remove(&event->node); /* mark as failed, if "add" event returns non-zero */ - if (event->exitstatus && strcmp(udev_device_get_action(event->dev), "add") == 0) - export_event_state(event, EVENT_FAILED); + if (event->exitcode && strcmp(udev_device_get_action(event->dev), "add") == 0) + udev_queue_export_device_failed(udev_queue_export, event->dev); else - export_event_state(event, EVENT_FINISHED); + udev_queue_export_device_finished(udev_queue_export, event->dev); + info(event->udev, "seq %llu done with %i\n", udev_device_get_seqnum(event->dev), event->exitcode); udev_device_unref(event->dev); - udev_event_unref(event); + free(event); +} + +static void event_sig_handler(int signum) +{ + switch (signum) { + case SIGALRM: + _exit(1); + break; + case SIGTERM: + worker_exit = 1; + break; + } } -static void asmlinkage event_sig_handler(int signum) +static void worker_unref(struct worker *worker) { - if (signum == SIGALRM) - exit(1); + udev_monitor_unref(worker->monitor); + free(worker); } -static void event_fork(struct udev_event *event) +static void worker_new(struct event *event) { + struct worker *worker; + struct udev_monitor *worker_monitor; pid_t pid; struct sigaction act; - int err; - if (debug_trace) { - event->trace = 1; - fprintf(stderr, "fork %s (%llu)\n", - udev_device_get_syspath(event->dev), - udev_device_get_seqnum(event->dev)); - } + /* listen for new events */ + worker_monitor = udev_monitor_new_from_netlink(event->udev, NULL); + if (worker_monitor == NULL) + return; + /* allow the main daemon netlink address to send devices to the worker */ + udev_monitor_allow_unicast_sender(worker_monitor, monitor); + udev_monitor_enable_receiving(worker_monitor); + util_set_fd_cloexec(udev_monitor_get_fd(worker_monitor)); + + worker = calloc(1, sizeof(struct worker)); + if (worker == NULL) + return; pid = fork(); switch (pid) { - case 0: - /* child */ - udev_monitor_unref(kernel_monitor); + case 0: { + sigset_t mask; + struct udev_device *dev; + + udev_queue_export_unref(udev_queue_export); + udev_monitor_unref(monitor); udev_ctrl_unref(udev_ctrl); + close(pfd[FD_SIGNAL].fd); + close(worker_watch[READ_END]); logging_close(); - logging_init("udevd-event"); + logging_init("udevd-work"); setpriority(PRIO_PROCESS, 0, UDEV_PRIORITY); /* set signal handlers */ memset(&act, 0x00, sizeof(act)); - act.sa_handler = (void (*)(int)) event_sig_handler; + act.sa_handler = event_sig_handler; sigemptyset (&act.sa_mask); act.sa_flags = 0; + sigaction(SIGTERM, &act, NULL); sigaction(SIGALRM, &act, NULL); - /* reset to default */ - act.sa_handler = SIG_DFL; - sigaction(SIGINT, &act, NULL); - sigaction(SIGTERM, &act, NULL); - sigaction(SIGCHLD, &act, NULL); - sigaction(SIGHUP, &act, NULL); + /* unblock signals */ + sigfillset(&mask); + sigdelset(&mask, SIGTERM); + sigdelset(&mask, SIGALRM); + sigprocmask(SIG_SETMASK, &mask, NULL); + + /* request TERM signal if parent exits */ + prctl(PR_SET_PDEATHSIG, SIGTERM); + + /* initial device */ + dev = event->dev; + + while (!worker_exit) { + struct udev_event *udev_event; + struct worker_message msg; + int err; - /* set timeout to prevent hanging processes */ - alarm(UDEV_EVENT_TIMEOUT); + udev_event = udev_event_new(dev); + if (udev_event == NULL) + _exit(3); - /* clear any existing udev watch on the node */ - if (inotify_fd != -1 && - major(udev_device_get_devnum(event->dev)) != 0) - udev_watch_clear(event->udev, event->dev); + /* set timeout to prevent hanging processes */ + alarm(UDEV_EVENT_TIMEOUT); - /* apply rules, create node, symlinks */ - err = udev_event_execute_rules(event, rules); + /* apply rules, create node, symlinks */ + err = udev_event_execute_rules(udev_event, rules); - /* rules may change/disable the timeout */ - if (udev_device_get_event_timeout(event->dev) >= 0) - alarm(udev_device_get_event_timeout(event->dev)); + /* rules may change/disable the timeout */ + if (udev_device_get_event_timeout(dev) >= 0) + alarm(udev_device_get_event_timeout(dev)); - /* execute RUN= */ - if (err == 0 && !event->ignore_device && udev_get_run(event->udev)) - udev_event_execute_run(event); + /* execute RUN= */ + if (err == 0 && !udev_event->ignore_device && udev_get_run(udev_event->udev)) + udev_event_execute_run(udev_event); + + /* reset alarm */ + alarm(0); + + /* apply/restore inotify watch */ + if (err == 0 && udev_event->inotify_watch) { + udev_watch_begin(udev_event->udev, dev); + udev_device_update_db(dev); + } - /* apply/restore inotify watch */ - if (err == 0 && event->inotify_watch && inotify_fd != -1 && - major(udev_device_get_devnum(event->dev)) != 0 && - strcmp(udev_device_get_action(event->dev), "remove") != 0) - info(event->udev, "device will be watched for changes\n"); - udev_watch_begin(event->udev, event->dev); + /* send processed event back to libudev listeners */ + udev_monitor_send_device(worker_monitor, NULL, dev); - info(event->udev, "seq %llu exit with %i\n", udev_device_get_seqnum(event->dev), err); + info(event->udev, "seq %llu processed with %i\n", udev_device_get_seqnum(dev), err); + udev_device_unref(dev); + udev_event_unref(udev_event); + + /* send back the result of the event execution */ + msg.exitcode = err; + msg.pid = getpid(); + send(worker_watch[WRITE_END], &msg, sizeof(struct worker_message), 0); + + /* wait for more device messages from udevd */ + do + dev = udev_monitor_receive_device(worker_monitor); + while (!worker_exit && dev == NULL); + } + + udev_monitor_unref(worker_monitor); logging_close(); - if (err != 0) - exit(1); exit(0); + } case -1: + udev_monitor_unref(worker_monitor); + event->state = EVENT_QUEUED; + free(worker); err(event->udev, "fork of child failed: %m\n"); - event_queue_delete(event); break; default: - /* get SIGCHLD in main loop */ - info(event->udev, "seq %llu forked, pid [%d], '%s' '%s', %ld seconds old\n", - udev_device_get_seqnum(event->dev), - pid, - udev_device_get_action(event->dev), - udev_device_get_subsystem(event->dev), - time(NULL) - event->queue_time); - event->pid = pid; + /* close monitor, but keep address around */ + udev_monitor_disconnect(worker_monitor); + worker->monitor = worker_monitor; + worker->pid = pid; + worker->state = WORKER_RUNNING; + worker->event = event; + event->state = EVENT_RUNNING; + udev_list_node_append(&worker->node, &worker_list); childs++; + break; } } -static void event_queue_insert(struct udev_event *event) +static void event_run(struct event *event) { - char filename[UTIL_PATH_SIZE]; - int fd; + struct udev_list_node *loop; - event->queue_time = time(NULL); + udev_list_node_foreach(loop, &worker_list) { + struct worker *worker = node_to_worker(loop); + ssize_t count; - export_event_state(event, EVENT_QUEUED); - info(event->udev, "seq %llu queued, '%s' '%s'\n", udev_device_get_seqnum(event->dev), - udev_device_get_action(event->dev), udev_device_get_subsystem(event->dev)); + if (worker->state != WORKER_IDLE) + continue; - util_strlcpy(filename, udev_get_dev_path(event->udev), sizeof(filename)); - util_strlcat(filename, "/.udev/uevent_seqnum", sizeof(filename)); - fd = open(filename, O_WRONLY|O_TRUNC|O_CREAT, 0644); - if (fd >= 0) { - char str[32]; - int len; + worker->event = event; + worker->state = WORKER_RUNNING; + event->state = EVENT_RUNNING; + count = udev_monitor_send_device(monitor, worker->monitor, event->dev); + if (count < 0) { + err(event->udev, "worker [%u] did not accept message, kill it\n", worker->pid); + event->state = EVENT_QUEUED; + worker->state = WORKER_KILLED; + kill(worker->pid, SIGKILL); + continue; + } + return; + } - len = sprintf(str, "%llu\n", udev_device_get_seqnum(event->dev)); - write(fd, str, len); - close(fd); + if (childs >= max_childs) { + info(event->udev, "maximum number (%i) of childs reached\n", childs); + return; } + /* start new worker and pass initial device */ + worker_new(event); +} + +static void event_queue_insert(struct udev_device *dev) +{ + struct event *event; + + event = calloc(1, sizeof(struct event)); + if (event == NULL) + return; + + event->udev = udev_device_get_udev(dev); + event->dev = dev; + event->seqnum = udev_device_get_seqnum(dev); + event->devpath = udev_device_get_devpath(dev); + event->devpath_len = strlen(event->devpath); + event->devpath_old = udev_device_get_devpath_old(dev); + + udev_queue_export_device_queued(udev_queue_export, dev); + info(event->udev, "seq %llu queued, '%s' '%s'\n", udev_device_get_seqnum(dev), + udev_device_get_action(dev), udev_device_get_subsystem(dev)); + event->state = EVENT_QUEUED; udev_list_node_append(&event->node, &event_list); - run_exec_q = 1; /* run all events with a timeout set immediately */ - if (udev_device_get_timeout(event->dev) > 0) { - event_fork(event); + if (udev_device_get_timeout(dev) > 0) { + worker_new(event); + return; + } +} + +static void worker_kill(int retain) +{ + struct udev_list_node *loop; + int max; + + if (childs <= retain) return; + + max = childs - retain; + + udev_list_node_foreach(loop, &worker_list) { + struct worker *worker = node_to_worker(loop); + + if (max-- <= 0) + break; + + if (worker->state == WORKER_KILLED) + continue; + + worker->state = WORKER_KILLED; + kill(worker->pid, SIGTERM); } } static int mem_size_mb(void) { - FILE* f; + FILE *f; char buf[4096]; long int memsize = -1; @@ -317,139 +421,111 @@ static int mem_size_mb(void) return memsize; } -static int compare_devpath(const char *running, const char *waiting) -{ - int i = 0; - - while (running[i] != '\0' && running[i] == waiting[i]) - i++; - - /* identical device event found */ - if (running[i] == '\0' && waiting[i] == '\0') - return 1; - - /* parent device event found */ - if (running[i] == '\0' && waiting[i] == '/') - return 2; - - /* child device event found */ - if (running[i] == '/' && waiting[i] == '\0') - return 3; - - /* no matching event */ - return 0; -} - -/* lookup event for identical, parent, child, or physical device */ -static int devpath_busy(struct udev_event *event) +/* lookup event for identical, parent, child device */ +static int devpath_busy(struct event *event) { struct udev_list_node *loop; + size_t common; - if (event->delaying_seqnum > 0) { - } /* check if queue contains events we depend on */ udev_list_node_foreach(loop, &event_list) { - struct udev_event *loop_event = node_to_event(loop); + struct event *loop_event = node_to_event(loop); /* we already found a later event, earlier can not block us, no need to check again */ - if (udev_device_get_seqnum(loop_event->dev) < event->delaying_seqnum) + if (loop_event->seqnum < event->delaying_seqnum) continue; /* event we checked earlier still exists, no need to check again */ - if (udev_device_get_seqnum(loop_event->dev) == event->delaying_seqnum) + if (loop_event->seqnum == event->delaying_seqnum) return 2; /* found ourself, no later event can block us */ - if (udev_device_get_seqnum(loop_event->dev) >= udev_device_get_seqnum(event->dev)) + if (loop_event->seqnum >= event->seqnum) break; /* check our old name */ - if (udev_device_get_devpath_old(event->dev) != NULL) - if (strcmp(udev_device_get_devpath(loop_event->dev), udev_device_get_devpath_old(event->dev)) == 0) { - event->delaying_seqnum = udev_device_get_seqnum(loop_event->dev); + if (event->devpath_old != NULL) + if (strcmp(loop_event->devpath, event->devpath_old) == 0) { + event->delaying_seqnum = loop_event->seqnum; return 3; } - /* check identical, parent, or child device event */ - if (compare_devpath(udev_device_get_devpath(loop_event->dev), udev_device_get_devpath(event->dev)) != 0) { - dbg(event->udev, "%llu, device event still pending %llu (%s)\n", - udev_device_get_seqnum(event->dev), - udev_device_get_seqnum(loop_event->dev), - udev_device_get_devpath(loop_event->dev)); - event->delaying_seqnum = udev_device_get_seqnum(loop_event->dev); + /* compare devpath */ + common = MIN(loop_event->devpath_len, event->devpath_len); + + /* one devpath is contained in the other? */ + if (memcmp(loop_event->devpath, event->devpath, common) != 0) + continue; + + /* identical device event found */ + if (loop_event->devpath_len == event->devpath_len) { + event->delaying_seqnum = loop_event->seqnum; return 4; } - /* check for our major:minor number */ - if (major(udev_device_get_devnum(event->dev)) > 0 && - udev_device_get_devnum(loop_event->dev) == udev_device_get_devnum(event->dev) && - strcmp(udev_device_get_subsystem(event->dev), udev_device_get_subsystem(loop_event->dev)) == 0) { - dbg(event->udev, "%llu, device event still pending %llu (%d:%d)\n", - udev_device_get_seqnum(event->dev), - udev_device_get_seqnum(loop_event->dev), - major(udev_device_get_devnum(loop_event->dev)), minor(udev_device_get_devnum(loop_event->dev))); - event->delaying_seqnum = udev_device_get_seqnum(loop_event->dev); + /* parent device event found */ + if (event->devpath[common] == '/') { + event->delaying_seqnum = loop_event->seqnum; return 5; } - /* check physical device event (special case of parent) */ - if (udev_device_get_physdevpath(event->dev) != NULL && - strcmp(udev_device_get_action(event->dev), "add") == 0) - if (compare_devpath(udev_device_get_devpath(loop_event->dev), - udev_device_get_physdevpath(event->dev)) != 0) { - dbg(event->udev, "%llu, physical device event still pending %llu (%s)\n", - udev_device_get_seqnum(event->dev), - udev_device_get_seqnum(loop_event->dev), - udev_device_get_devpath(loop_event->dev)); - event->delaying_seqnum = udev_device_get_seqnum(loop_event->dev); - return 6; - } + /* child device event found */ + if (loop_event->devpath[common] == '/') { + event->delaying_seqnum = loop_event->seqnum; + return 6; + } + + /* no matching device */ + continue; } + return 0; } -/* serializes events for the identical and parent and child devices */ -static void event_queue_manager(struct udev *udev) +static void events_start(struct udev *udev) { struct udev_list_node *loop; - struct udev_list_node *tmp; -start_over: - if (udev_list_is_empty(&event_list)) { - if (childs > 0) { - err(udev, "event list empty, but childs count is %i", childs); - childs = 0; - } - return; - } - - udev_list_node_foreach_safe(loop, tmp, &event_list) { - struct udev_event *loop_event = node_to_event(loop); - - if (childs >= max_childs) { - info(udev, "maximum number (%i) of childs reached\n", childs); - break; - } + udev_list_node_foreach(loop, &event_list) { + struct event *event = node_to_event(loop); - if (loop_event->pid != 0) + if (event->state != EVENT_QUEUED) continue; /* do not start event if parent or child event is still running */ - if (devpath_busy(loop_event) != 0) { - dbg(udev, "delay seq %llu (%s)\n", - udev_device_get_seqnum(loop_event->dev), - udev_device_get_devpath(loop_event->dev)); + if (devpath_busy(event) != 0) { + dbg(udev, "delay seq %llu (%s)\n", event->seqnum, event->devpath); continue; } - event_fork(loop_event); - dbg(udev, "moved seq %llu to running list\n", udev_device_get_seqnum(loop_event->dev)); + event_run(event); + } +} + +static void worker_returned(void) +{ + while (1) { + struct worker_message msg; + ssize_t size; + struct udev_list_node *loop; + + size = recv(pfd[FD_WORKER].fd, &msg, sizeof(struct worker_message), MSG_DONTWAIT); + if (size != sizeof(struct worker_message)) + break; - /* retry if events finished in the meantime */ - if (sigchilds_waiting) { - sigchilds_waiting = 0; - reap_sigchilds(); - goto start_over; + /* lookup worker who sent the signal */ + udev_list_node_foreach(loop, &worker_list) { + struct worker *worker = node_to_worker(loop); + + if (worker->pid != msg.pid) + continue; + + /* worker returned */ + worker->event->exitcode = msg.exitcode; + event_queue_delete(worker->event); + worker->event = NULL; + worker->state = WORKER_IDLE; + break; } } } @@ -470,17 +546,17 @@ static void handle_ctrl_msg(struct udev_ctrl *uctrl) if (i >= 0) { info(udev, "udevd message (SET_LOG_PRIORITY) received, log_priority=%i\n", i); udev_set_log_priority(udev, i); + worker_kill(0); } if (udev_ctrl_get_stop_exec_queue(ctrl_msg) > 0) { info(udev, "udevd message (STOP_EXEC_QUEUE) received\n"); - stop_exec_q = 1; + stop_exec_queue = 1; } if (udev_ctrl_get_start_exec_queue(ctrl_msg) > 0) { info(udev, "udevd message (START_EXEC_QUEUE) received\n"); - stop_exec_q = 0; - event_queue_manager(udev); + stop_exec_queue = 0; } if (udev_ctrl_get_reload_rules(ctrl_msg) > 0) { @@ -512,6 +588,7 @@ static void handle_ctrl_msg(struct udev_ctrl *uctrl) } free(key); } + worker_kill(0); } i = udev_ctrl_get_set_max_childs(ctrl_msg); @@ -519,190 +596,153 @@ static void handle_ctrl_msg(struct udev_ctrl *uctrl) info(udev, "udevd message (SET_MAX_CHILDS) received, max_childs=%i\n", i); max_childs = i; } + + settle_pid = udev_ctrl_get_settle(ctrl_msg); + if (settle_pid > 0) { + info(udev, "udevd message (SETTLE) received\n"); + kill(settle_pid, SIGUSR1); + settle_pid = 0; + } udev_ctrl_msg_unref(ctrl_msg); } /* read inotify messages */ static int handle_inotify(struct udev *udev) { - int nbytes, pos; + ssize_t nbytes, pos; char *buf; struct inotify_event *ev; - if ((ioctl(inotify_fd, FIONREAD, &nbytes) < 0) || (nbytes <= 0)) + if ((ioctl(pfd[FD_INOTIFY].fd, FIONREAD, &nbytes) < 0) || (nbytes <= 0)) return 0; buf = malloc(nbytes); if (buf == NULL) { - err(udev, "error getting buffer for inotify, disable watching\n"); - close(inotify_fd); - inotify_fd = -1; - return 0; + err(udev, "error getting buffer for inotify\n"); + return -1; } - read(inotify_fd, buf, nbytes); + nbytes = read(pfd[FD_INOTIFY].fd, buf, nbytes); - for (pos = 0, ev = (struct inotify_event *)(buf + pos); pos < nbytes; pos += sizeof(struct inotify_event) + ev->len) { - const char *syspath; + for (pos = 0; pos < nbytes; pos += sizeof(struct inotify_event) + ev->len) { + struct udev_device *dev; - dbg(udev, "inotify event: %x for %d (%s)\n", ev->mask, ev->wd, ev->len ? ev->name : "*"); + ev = (struct inotify_event *)(buf + pos); + if (ev->len) { + dbg(udev, "inotify event: %x for %s\n", ev->mask, ev->name); + reload_config = 1; + continue; + } - syspath = udev_watch_lookup(udev, ev->wd); - if (syspath != NULL) { - dbg(udev, "inotify event: %x for %s\n", ev->mask, syspath); + dev = udev_watch_lookup(udev, ev->wd); + if (dev != NULL) { + dbg(udev, "inotify event: %x for %s\n", ev->mask, udev_device_get_devnode(dev)); if (ev->mask & IN_CLOSE_WRITE) { char filename[UTIL_PATH_SIZE]; int fd; - info(udev, "device %s closed, synthesising 'change'\n", syspath); - util_strlcpy(filename, syspath, sizeof(filename)); - util_strlcat(filename, "/uevent", sizeof(filename)); + info(udev, "device %s closed, synthesising 'change'\n", udev_device_get_devnode(dev)); + util_strscpyl(filename, sizeof(filename), udev_device_get_syspath(dev), "/uevent", NULL); fd = open(filename, O_WRONLY); if (fd < 0 || write(fd, "change", 6) < 0) info(udev, "error writing uevent: %m\n"); close(fd); } if (ev->mask & IN_IGNORED) - udev_watch_end(udev, ev->wd); - } else { - reload_config = 1; - } - } + udev_watch_end(udev, dev); - free (buf); - return 0; -} + udev_device_unref(dev); + } -static void asmlinkage sig_handler(int signum) -{ - switch (signum) { - case SIGINT: - case SIGTERM: - udev_exit = 1; - break; - case SIGCHLD: - /* set flag, then write to pipe if needed */ - sigchilds_waiting = 1; - break; - case SIGHUP: - reload_config = 1; - break; } - signal_received = 1; -} - -static void udev_done(int pid, int exitstatus) -{ - struct udev_list_node *loop; - - /* find event associated with pid and delete it */ - udev_list_node_foreach(loop, &event_list) { - struct udev_event *loop_event = node_to_event(loop); - - if (loop_event->pid == pid) { - info(loop_event->udev, "seq %llu cleanup, pid [%d], status %i, %ld seconds old\n", - udev_device_get_seqnum(loop_event->dev), loop_event->pid, - exitstatus, time(NULL) - loop_event->queue_time); - loop_event->exitstatus = exitstatus; - if (debug_trace) - fprintf(stderr, "exit %s (%llu)\n", - udev_device_get_syspath(loop_event->dev), - udev_device_get_seqnum(loop_event->dev)); - event_queue_delete(loop_event); - childs--; - - /* there may be dependent events waiting */ - run_exec_q = 1; - return; - } - } + free(buf); + return 0; } -static void reap_sigchilds(void) +static void handle_signal(struct udev *udev, int signo) { - pid_t pid; - int status; + switch (signo) { + case SIGINT: + case SIGTERM: + udev_exit = 1; + break; + case SIGCHLD: + while (1) { + pid_t pid; + int status; + struct udev_list_node *loop, *tmp; - while (1) { - pid = waitpid(-1, &status, WNOHANG); - if (pid <= 0) - break; - if (WIFEXITED(status)) - status = WEXITSTATUS(status); - else if (WIFSIGNALED(status)) - status = WTERMSIG(status) + 128; - else - status = 0; - udev_done(pid, status); - } -} + pid = waitpid(-1, &status, WNOHANG); + if (pid <= 0) + break; -static void cleanup_queue_dir(struct udev *udev) -{ - char dirname[UTIL_PATH_SIZE]; - char filename[UTIL_PATH_SIZE]; - DIR *dir; - - util_strlcpy(filename, udev_get_dev_path(udev), sizeof(filename)); - util_strlcat(filename, "/.udev/uevent_seqnum", sizeof(filename)); - unlink(filename); - - util_strlcpy(dirname, udev_get_dev_path(udev), sizeof(dirname)); - util_strlcat(dirname, "/.udev/queue", sizeof(dirname)); - dir = opendir(dirname); - if (dir != NULL) { - while (1) { - struct dirent *dent; + udev_list_node_foreach_safe(loop, tmp, &worker_list) { + struct worker *worker = node_to_worker(loop); + + if (worker->pid != pid) + continue; + + /* fail event, if worker died unexpectedly */ + if (worker->event != NULL) { + int exitcode; + + if (WIFEXITED(status)) + exitcode = WEXITSTATUS(status); + else if (WIFSIGNALED(status)) + exitcode = WTERMSIG(status) + 128; + else + exitcode = 0; + worker->event->exitcode = exitcode; + err(udev, "worker [%u] unexpectedly returned with %i\n", pid, exitcode); + event_queue_delete(worker->event); + } - dent = readdir(dir); - if (dent == NULL || dent->d_name[0] == '\0') + udev_list_node_remove(&worker->node); + worker_unref(worker); + childs--; break; - if (dent->d_name[0] == '.') - continue; - util_strlcpy(filename, dirname, sizeof(filename)); - util_strlcat(filename, "/", sizeof(filename)); - util_strlcat(filename, dent->d_name, sizeof(filename)); - unlink(filename); + } } - closedir(dir); - rmdir(dirname); + break; + case SIGHUP: + reload_config = 1; + break; } } -static void export_initial_seqnum(struct udev *udev) +static void startup_log(struct udev *udev) { - char filename[UTIL_PATH_SIZE]; - int fd; - char seqnum[32]; - ssize_t len = 0; - - util_strlcpy(filename, udev_get_sys_path(udev), sizeof(filename)); - util_strlcat(filename, "/kernel/uevent_seqnum", sizeof(filename)); - fd = open(filename, O_RDONLY); - if (fd >= 0) { - len = read(fd, seqnum, sizeof(seqnum)-1); - close(fd); - } - if (len <= 0) { - strcpy(seqnum, "0\n"); - len = 3; - } - util_strlcpy(filename, udev_get_dev_path(udev), sizeof(filename)); - util_strlcat(filename, "/.udev/uevent_seqnum", sizeof(filename)); - util_create_path(udev, filename); - fd = open(filename, O_WRONLY|O_TRUNC|O_CREAT, 0644); - if (fd >= 0) { - write(fd, seqnum, len); - close(fd); + FILE *f; + char path[UTIL_PATH_SIZE]; + struct stat statbuf; + + f = fopen("/dev/kmsg", "w"); + if (f != NULL) + fprintf(f, "<6>udev: starting version " VERSION "\n"); + + util_strscpyl(path, sizeof(path), udev_get_sys_path(udev), "/class/mem/null", NULL); + if (lstat(path, &statbuf) == 0 && S_ISDIR(statbuf.st_mode)) { + const char *depr_str = + "udev: missing sysfs features; please update the kernel " + "or disable the kernel's CONFIG_SYSFS_DEPRECATED option; " + "udev may fail to work correctly"; + + if (f != NULL) + fprintf(f, "<3>%s\n", depr_str); + err(udev, "%s\n", depr_str); + sleep(3); } + + if (f != NULL) + fclose(f); } int main(int argc, char *argv[]) { struct udev *udev; int fd; - struct sigaction act; + sigset_t mask; const char *value; int daemonize = 0; int resolve_names = 1; @@ -795,31 +835,82 @@ int main(int argc, char *argv[]) rc = 1; goto exit; } - if (udev_ctrl_enable_receiving(udev_ctrl) < 0) { fprintf(stderr, "error binding control socket, seems udevd is already running\n"); err(udev, "error binding control socket, seems udevd is already running\n"); rc = 1; goto exit; } + pfd[FD_CONTROL].fd = udev_ctrl_get_fd(udev_ctrl); - kernel_monitor = udev_monitor_new_from_netlink(udev); - if (kernel_monitor == NULL || udev_monitor_enable_receiving(kernel_monitor) < 0) { + monitor = udev_monitor_new_from_netlink(udev, "kernel"); + if (monitor == NULL || udev_monitor_enable_receiving(monitor) < 0) { fprintf(stderr, "error initializing netlink socket\n"); err(udev, "error initializing netlink socket\n"); rc = 3; goto exit; } - udev_monitor_set_receive_buffer_size(kernel_monitor, 128*1024*1024); + udev_monitor_set_receive_buffer_size(monitor, 128*1024*1024); + pfd[FD_NETLINK].fd = udev_monitor_get_fd(monitor); + + pfd[FD_INOTIFY].fd = udev_watch_init(udev); + if (pfd[FD_INOTIFY].fd < 0) { + fprintf(stderr, "error initializing inotify\n"); + err(udev, "error initializing inotify\n"); + rc = 4; + goto exit; + } + + if (udev_get_rules_path(udev) != NULL) { + inotify_add_watch(pfd[FD_INOTIFY].fd, udev_get_rules_path(udev), + IN_CREATE | IN_DELETE | IN_MOVE | IN_CLOSE_WRITE); + } else { + char filename[UTIL_PATH_SIZE]; + + inotify_add_watch(pfd[FD_INOTIFY].fd, UDEV_PREFIX "/lib/udev/rules.d", + IN_CREATE | IN_DELETE | IN_MOVE | IN_CLOSE_WRITE); + inotify_add_watch(pfd[FD_INOTIFY].fd, SYSCONFDIR "/udev/rules.d", + IN_CREATE | IN_DELETE | IN_MOVE | IN_CLOSE_WRITE); + + /* watch dynamic rules directory */ + util_strscpyl(filename, sizeof(filename), udev_get_dev_path(udev), "/.udev/rules.d", NULL); + inotify_add_watch(pfd[FD_INOTIFY].fd, filename, + IN_CREATE | IN_DELETE | IN_MOVE | IN_CLOSE_WRITE); + } + udev_watch_restore(udev); + + /* block and listen to all signals on signalfd */ + sigfillset(&mask); + sigprocmask(SIG_SETMASK, &mask, NULL); + pfd[FD_SIGNAL].fd = signalfd(-1, &mask, 0); + if (pfd[FD_SIGNAL].fd < 0) { + fprintf(stderr, "error getting signalfd\n"); + err(udev, "error getting signalfd\n"); + rc = 5; + goto exit; + } + + /* unnamed socket from workers to the main daemon */ + if (socketpair(AF_LOCAL, SOCK_DGRAM, 0, worker_watch) < 0) { + fprintf(stderr, "error getting socketpair\n"); + err(udev, "error getting socketpair\n"); + rc = 6; + goto exit; + } + pfd[FD_WORKER].fd = worker_watch[READ_END]; + util_set_fd_cloexec(worker_watch[WRITE_END]); rules = udev_rules_new(udev, resolve_names); if (rules == NULL) { err(udev, "error reading rules\n"); goto exit; } - udev_list_init(&event_list); - cleanup_queue_dir(udev); - export_initial_seqnum(udev); + + udev_queue_export = udev_queue_export_new(udev); + if (udev_queue_export == NULL) { + err(udev, "error creating queue file\n"); + goto exit; + } if (daemonize) { pid_t pid; @@ -827,19 +918,19 @@ int main(int argc, char *argv[]) pid = fork(); switch (pid) { case 0: - dbg(udev, "daemonized fork running\n"); break; case -1: err(udev, "fork of daemon failed: %m\n"); rc = 4; goto exit; default: - dbg(udev, "child [%u] running, parent exits\n", pid); rc = 0; goto exit; } } + startup_log(udev); + /* redirect std{out,err} */ if (!debug && !debug_trace) { dup2(fd, STDIN_FILENO); @@ -858,180 +949,122 @@ int main(int argc, char *argv[]) /* OOM_DISABLE == -17 */ fd = open("/proc/self/oom_adj", O_RDWR); - if (fd < 0) + if (fd < 0) { err(udev, "error disabling OOM: %m\n"); - else { + } else { write(fd, "-17", 3); close(fd); } - fd = open("/dev/kmsg", O_WRONLY); - if (fd > 0) { - const char *ver_str = "<6>udev: starting version " VERSION "\n"; - char path[UTIL_PATH_SIZE]; - struct stat statbuf; - - write(fd, ver_str, strlen(ver_str)); - util_strlcpy(path, udev_get_sys_path(udev), sizeof(path)); - util_strlcat(path, "/class/mem/null", sizeof(path)); - if (lstat(path, &statbuf) == 0) { - if (S_ISDIR(statbuf.st_mode)) { - const char *depr_str = - "<6>udev: deprecated sysfs layout; update the kernel or " - "disable CONFIG_SYSFS_DEPRECATED; some udev features will " - "not work correctly\n"; - - write(fd, depr_str, strlen(depr_str)); - } - } - close(fd); - } - - /* set signal handlers */ - memset(&act, 0x00, sizeof(struct sigaction)); - act.sa_handler = (void (*)(int)) sig_handler; - sigemptyset(&act.sa_mask); - act.sa_flags = SA_RESTART; - sigaction(SIGINT, &act, NULL); - sigaction(SIGTERM, &act, NULL); - sigaction(SIGCHLD, &act, NULL); - sigaction(SIGHUP, &act, NULL); - - /* watch rules directory */ - udev_watch_init(udev); - if (inotify_fd >= 0) { - if (udev_get_rules_path(udev) != NULL) { - inotify_add_watch(inotify_fd, udev_get_rules_path(udev), - IN_CREATE | IN_DELETE | IN_MOVE | IN_CLOSE_WRITE); - } else { - char filename[UTIL_PATH_SIZE]; - - inotify_add_watch(inotify_fd, UDEV_PREFIX "/lib/udev/rules.d", - IN_CREATE | IN_DELETE | IN_MOVE | IN_CLOSE_WRITE); - inotify_add_watch(inotify_fd, SYSCONFDIR "/udev/rules.d", - IN_CREATE | IN_DELETE | IN_MOVE | IN_CLOSE_WRITE); - - /* watch dynamic rules directory */ - util_strlcpy(filename, udev_get_dev_path(udev), sizeof(filename)); - util_strlcat(filename, "/.udev/rules.d", sizeof(filename)); - inotify_add_watch(inotify_fd, filename, - IN_CREATE | IN_DELETE | IN_MOVE | IN_CLOSE_WRITE); - } - - udev_watch_restore(udev); - } - /* in trace mode run one event after the other */ if (debug_trace) { max_childs = 1; } else { int memsize = mem_size_mb(); + if (memsize > 0) - max_childs = 128 + (memsize / 4); + max_childs = 128 + (memsize / 8); else - max_childs = UDEVD_MAX_CHILDS; + max_childs = 128; } + /* possibly overwrite maximum limit of executed events */ value = getenv("UDEVD_MAX_CHILDS"); if (value) max_childs = strtoul(value, NULL, 10); info(udev, "initialize max_childs to %u\n", max_childs); + udev_list_init(&event_list); + udev_list_init(&worker_list); + while (!udev_exit) { - sigset_t blocked_mask, orig_mask; - struct pollfd pfd[4]; - struct pollfd *ctrl_poll, *monitor_poll, *inotify_poll = NULL; - int nfds = 0; int fdcount; + int timeout; - sigfillset(&blocked_mask); - sigprocmask(SIG_SETMASK, &blocked_mask, &orig_mask); - if (signal_received) { - sigprocmask(SIG_SETMASK, &orig_mask, NULL); - goto handle_signals; - } + /* set timeout to kill idle workers */ + if (udev_list_is_empty(&event_list) && childs > 2) + timeout = 3 * 1000; + else + timeout = -1; + /* wait for events */ + fdcount = poll(pfd, ARRAY_SIZE(pfd), timeout); + if (fdcount < 0) + continue; - ctrl_poll = &pfd[nfds++]; - ctrl_poll->fd = udev_ctrl_get_fd(udev_ctrl); - ctrl_poll->events = POLLIN; + /* timeout - kill idle workers */ + if (fdcount == 0) + worker_kill(2); - monitor_poll = &pfd[nfds++]; - monitor_poll->fd = udev_monitor_get_fd(kernel_monitor); - monitor_poll->events = POLLIN; + /* event has finished */ + if (pfd[FD_WORKER].revents & POLLIN) + worker_returned(); - if (inotify_fd >= 0) { - inotify_poll = &pfd[nfds++]; - inotify_poll->fd = inotify_fd; - inotify_poll->events = POLLIN; - } + /* get kernel uevent */ + if (pfd[FD_NETLINK].revents & POLLIN) { + struct udev_device *dev; - fdcount = ppoll(pfd, nfds, NULL, &orig_mask); - sigprocmask(SIG_SETMASK, &orig_mask, NULL); - if (fdcount < 0) { - if (errno == EINTR) - goto handle_signals; - err(udev, "error in select: %m\n"); - continue; + dev = udev_monitor_receive_device(monitor); + if (dev != NULL) + event_queue_insert(dev); + else + udev_device_unref(dev); } - /* get control message */ - if (ctrl_poll->revents & POLLIN) - handle_ctrl_msg(udev_ctrl); - - /* get kernel uevent */ - if (monitor_poll->revents & POLLIN) { - struct udev_device *dev; + /* start new events */ + if (!udev_list_is_empty(&event_list) && !stop_exec_queue) + events_start(udev); - dev = udev_monitor_receive_device(kernel_monitor); - if (dev != NULL) { - struct udev_event *event; + /* get signal */ + if (pfd[FD_SIGNAL].revents & POLLIN) { + struct signalfd_siginfo fdsi; + ssize_t size; - event = udev_event_new(dev); - if (event != NULL) - event_queue_insert(event); - else - udev_device_unref(dev); - } + size = read(pfd[FD_SIGNAL].fd, &fdsi, sizeof(struct signalfd_siginfo)); + if (size == sizeof(struct signalfd_siginfo)) + handle_signal(udev, fdsi.ssi_signo); } - /* rules directory inotify watch */ - if (inotify_poll && (inotify_poll->revents & POLLIN)) + /* device node and rules directory inotify watch */ + if (pfd[FD_INOTIFY].revents & POLLIN) handle_inotify(udev); -handle_signals: - signal_received = 0; + /* + * get control message + * + * This needs to be after the inotify handling, to make sure, + * that the settle signal is send back after the possibly generated + * "change" events by the inotify device node watch. + */ + if (pfd[FD_CONTROL].revents & POLLIN) + handle_ctrl_msg(udev_ctrl); /* rules changed, set by inotify or a HUP signal */ if (reload_config) { struct udev_rules *rules_new; - reload_config = 0; + worker_kill(0); rules_new = udev_rules_new(udev, resolve_names); if (rules_new != NULL) { udev_rules_unref(rules); rules = rules_new; } - } - - if (sigchilds_waiting) { - sigchilds_waiting = 0; - reap_sigchilds(); - } - - if (run_exec_q) { - run_exec_q = 0; - if (!stop_exec_q) - event_queue_manager(udev); + reload_config = 0; } } - cleanup_queue_dir(udev); + + udev_queue_export_cleanup(udev_queue_export); rc = 0; exit: + udev_queue_export_unref(udev_queue_export); udev_rules_unref(rules); udev_ctrl_unref(udev_ctrl); - if (inotify_fd >= 0) - close(inotify_fd); - udev_monitor_unref(kernel_monitor); + if (pfd[FD_SIGNAL].fd >= 0) + close(pfd[FD_SIGNAL].fd); + if (worker_watch[READ_END] >= 0) + close(worker_watch[READ_END]); + if (worker_watch[WRITE_END] >= 0) + close(worker_watch[WRITE_END]); + udev_monitor_unref(monitor); udev_selinux_exit(udev); udev_unref(udev); logging_close();