From 9ea28c55a2488e6cd4a44ac5786f12b71ad5bc9f Mon Sep 17 00:00:00 2001 From: Kay Sievers Date: Sat, 12 Apr 2014 22:35:50 -0700 Subject: udev: remove seqnum API and all assumptions about seqnums The way the kernel namespaces have been implemented breaks assumptions udev made regarding uevent sequence numbers. Creating devices in a namespace "steals" uevents and its sequence numbers from the host. It confuses the "udevadmin settle" logic, which might block until util a timeout is reached, even when no uevent is pending. Remove any assumptions about sequence numbers and deprecate libudev's API exposing these numbers; none of that can reliably be used anymore when namespaces are involved. --- src/udev/udev-ctrl.c | 2 +- src/udev/udevadm-settle.c | 131 ++++++++-------------------------------------- src/udev/udevd.c | 59 ++++++++++----------- 3 files changed, 51 insertions(+), 141 deletions(-) (limited to 'src/udev') diff --git a/src/udev/udev-ctrl.c b/src/udev/udev-ctrl.c index 1e91ec20a1..74bbd3a99e 100644 --- a/src/udev/udev-ctrl.c +++ b/src/udev/udev-ctrl.c @@ -275,7 +275,7 @@ static int ctrl_send(struct udev_ctrl *uctrl, enum udev_ctrl_msg_type type, int pfd[0].fd = uctrl->sock; pfd[0].events = POLLIN; - r = poll(pfd, 1, timeout * 1000); + r = poll(pfd, 1, timeout * MSEC_PER_SEC); if (r < 0) { if (errno == EINTR) continue; diff --git a/src/udev/udevadm-settle.c b/src/udev/udevadm-settle.c index 927ea2a7f2..65fc35f9a0 100644 --- a/src/udev/udevadm-settle.c +++ b/src/udev/udevadm-settle.c @@ -41,42 +41,28 @@ static void help(void) { printf("Usage: udevadm settle OPTIONS\n" " -t,--timeout= maximum time to wait for events\n" - " -s,--seq-start= first seqnum to wait for\n" - " -e,--seq-end= last seqnum to wait for\n" " -E,--exit-if-exists= stop waiting if file exists\n" - " -q,--quiet do not print list after timeout\n" " -h,--help\n\n"); } static int adm_settle(struct udev *udev, int argc, char *argv[]) { static const struct option options[] = { - { "seq-start", required_argument, NULL, 's' }, - { "seq-end", required_argument, NULL, 'e' }, + { "seq-start", required_argument, NULL, '\0' }, /* removed */ + { "seq-end", required_argument, NULL, '\0' }, /* removed */ { "timeout", required_argument, NULL, 't' }, { "exit-if-exists", required_argument, NULL, 'E' }, - { "quiet", no_argument, NULL, 'q' }, + { "quiet", no_argument, NULL, 'q' }, /* removed */ { "help", no_argument, NULL, 'h' }, {} }; - usec_t start_usec = now(CLOCK_MONOTONIC); - usec_t start = 0; - usec_t end = 0; - int quiet = 0; const char *exists = NULL; unsigned int timeout = 120; struct pollfd pfd[1] = { {.fd = -1}, }; - _cleanup_udev_queue_unref_ struct udev_queue *udev_queue = NULL; int rc = EXIT_FAILURE, c; - while ((c = getopt_long(argc, argv, "s:e:t:E:qh", options, NULL)) >= 0) + while ((c = getopt_long(argc, argv, "s:e:t:E:qh", options, NULL)) >= 0) { switch (c) { - case 's': - start = strtoull(optarg, NULL, 0); - break; - case 'e': - end = strtoull(optarg, NULL, 0); - break; case 't': { int r; @@ -91,9 +77,6 @@ static int adm_settle(struct udev *udev, int argc, char *argv[]) case 'E': exists = optarg; break; - case 'q': - quiet = 1; - break; case 'h': help(); exit(EXIT_SUCCESS); @@ -102,44 +85,13 @@ static int adm_settle(struct udev *udev, int argc, char *argv[]) default: assert_not_reached("Unknown argument"); } + } if (optind < argc) { fprintf(stderr, "Extraneous argument: '%s'\n", argv[optind]); exit(EXIT_FAILURE); } - udev_queue = udev_queue_new(udev); - if (udev_queue == NULL) - exit(2); - - if (start > 0) { - unsigned long long kernel_seq; - - kernel_seq = udev_queue_get_kernel_seqnum(udev_queue); - - /* unless specified, the last event is the current kernel seqnum */ - if (end == 0) - end = udev_queue_get_kernel_seqnum(udev_queue); - - if (start > end) { - log_error("seq-start larger than seq-end, ignoring"); - start = 0; - end = 0; - } - - if (start > kernel_seq || end > kernel_seq) { - log_error("seq-start or seq-end larger than current kernel value, ignoring"); - start = 0; - end = 0; - } - log_debug("start=%llu end=%llu current=%llu", (unsigned long long)start, (unsigned long long)end, kernel_seq); - } else { - if (end > 0) { - log_error("seq-end needs seq-start parameter, ignoring"); - end = 0; - } - } - /* guarantee that the udev daemon isn't pre-processing */ if (getuid() == 0) { struct udev_ctrl *uctrl; @@ -160,73 +112,34 @@ static int adm_settle(struct udev *udev, int argc, char *argv[]) pfd[0].fd = inotify_init1(IN_CLOEXEC); if (pfd[0].fd < 0) { log_error("inotify_init failed: %m"); - } else { - if (inotify_add_watch(pfd[0].fd, "/run/udev" , IN_MOVED_TO) < 0) { - log_error("watching /run/udev failed"); - close(pfd[0].fd); - pfd[0].fd = -1; - } + goto out; } - for (;;) { - struct stat statbuf; + if (inotify_add_watch(pfd[0].fd, "/run/udev/queue" , IN_DELETE) < 0) { + log_debug("watching /run/udev failed"); + goto out; + } - if (exists != NULL && stat(exists, &statbuf) == 0) { + for (;;) { + if (exists && access(exists, F_OK) >= 0) { rc = EXIT_SUCCESS; break; } - if (start > 0) { - /* if asked for, wait for a specific sequence of events */ - if (udev_queue_get_seqnum_sequence_is_finished(udev_queue, start, end) == 1) { - rc = EXIT_SUCCESS; - break; - } - } else { - /* exit if queue is empty */ - if (udev_queue_get_queue_is_empty(udev_queue)) { - rc = EXIT_SUCCESS; - break; - } - } - - if (pfd[0].fd >= 0) { - int delay; - - if (exists != NULL || start > 0) - delay = 100; - else - delay = 1000; - /* wake up after delay, or immediately after the queue is rebuilt */ - if (poll(pfd, 1, delay) > 0 && pfd[0].revents & POLLIN) { - char buf[sizeof(struct inotify_event) + PATH_MAX]; - - read(pfd[0].fd, buf, sizeof(buf)); - } - } else { - sleep(1); + /* exit if queue is empty */ + if (access("/run/udev/queue", F_OK) < 0) { + rc = EXIT_SUCCESS; + break; } - if (timeout > 0) { - usec_t age_usec; + /* wake up when "queue" file is deleted */ + if (poll(pfd, 1, 100) > 0 && pfd[0].revents & POLLIN) { + char buf[sizeof(struct inotify_event) + PATH_MAX]; - age_usec = now(CLOCK_MONOTONIC) - start_usec; - if (age_usec / (1000 * 1000) >= timeout) { - struct udev_list_entry *list_entry; - - if (!quiet && udev_queue_get_queued_list_entry(udev_queue) != NULL) { - log_debug("timeout waiting for udev queue"); - printf("\nudevadm settle - timeout of %i seconds reached, the event queue contains:\n", timeout); - udev_list_entry_foreach(list_entry, udev_queue_get_queued_list_entry(udev_queue)) - printf(" %s (%s)\n", - udev_list_entry_get_name(list_entry), - udev_list_entry_get_value(list_entry)); - } - - break; - } + read(pfd[0].fd, buf, sizeof(buf)); } } + out: if (pfd[0].fd >= 0) close(pfd[0].fd); @@ -236,5 +149,5 @@ out: const struct udevadm_cmd udevadm_settle = { .name = "settle", .cmd = adm_settle, - .help = "wait for the event queue to finish", + .help = "wait for pending udev events", }; diff --git a/src/udev/udevd.c b/src/udev/udevd.c index f21c227d17..f9ee36870b 100644 --- a/src/udev/udevd.c +++ b/src/udev/udevd.c @@ -60,7 +60,6 @@ void udev_main_log(struct udev *udev, int priority, } static struct udev_rules *rules; -static struct udev_queue_export *udev_queue_export; static struct udev_ctrl *udev_ctrl; static struct udev_monitor *monitor; static int worker_watch[2] = { -1, -1 }; @@ -139,14 +138,9 @@ static inline struct worker *node_to_worker(struct udev_list_node *node) return container_of(node, struct worker, node); } -static void event_queue_delete(struct event *event, bool export) +static void event_queue_delete(struct event *event) { udev_list_node_remove(&event->node); - - if (export) { - udev_queue_export_device_finished(udev_queue_export, event->dev); - log_debug("seq %llu done with %i", udev_device_get_seqnum(event->dev), event->exitcode); - } udev_device_unref(event->dev); free(event); } @@ -225,7 +219,6 @@ static void worker_new(struct event *event) free(worker); worker_list_cleanup(udev); event_queue_cleanup(udev, EVENT_UNDEF); - udev_queue_export_unref(udev_queue_export); udev_monitor_unref(monitor); udev_ctrl_unref(udev_ctrl); close(fd_signal); @@ -449,7 +442,6 @@ static int event_queue_insert(struct udev_device *dev) event->nodelay = true; #endif - udev_queue_export_device_queued(udev_queue_export, dev); log_debug("seq %llu queued, '%s' '%s'", udev_device_get_seqnum(dev), udev_device_get_action(dev), udev_device_get_subsystem(dev)); @@ -580,7 +572,7 @@ static void event_queue_cleanup(struct udev *udev, enum event_state match_type) if (match_type != EVENT_UNDEF && match_type != event->state) continue; - event_queue_delete(event, false); + event_queue_delete(event); } } @@ -605,7 +597,7 @@ static void worker_returned(int fd_worker) /* worker returned */ if (worker->event) { worker->event->exitcode = msg.exitcode; - event_queue_delete(worker->event, true); + event_queue_delete(worker->event); worker->event = NULL; } if (worker->state != WORKER_KILLED) @@ -797,7 +789,8 @@ static void handle_signal(struct udev *udev, int signo) log_error("worker [%u] failed while handling '%s'", pid, worker->event->devpath); worker->event->exitcode = -32; - event_queue_delete(worker->event, true); + event_queue_delete(worker->event); + /* drop reference taken for state 'running' */ worker_unref(worker); } @@ -1076,14 +1069,7 @@ int main(int argc, char *argv[]) goto exit; } - udev_monitor_set_receive_buffer_size(monitor, 128*1024*1024); - - /* create queue file before signalling 'ready', to make sure we block 'settle' */ - udev_queue_export = udev_queue_export_new(udev); - if (udev_queue_export == NULL) { - log_error("error creating queue file"); - goto exit; - } + udev_monitor_set_receive_buffer_size(monitor, 128 * 1024 * 1024); if (daemonize) { pid_t pid; @@ -1241,12 +1227,12 @@ int main(int argc, char *argv[]) worker_kill(udev); /* exit after all has cleaned up */ - if (udev_list_node_is_empty(&event_list) && udev_list_node_is_empty(&worker_list)) + if (udev_list_node_is_empty(&event_list) && children == 0) break; /* timeout at exit for workers to finish */ - timeout = 30 * 1000; - } else if (udev_list_node_is_empty(&event_list) && !children) { + timeout = 30 * MSEC_PER_SEC; + } else if (udev_list_node_is_empty(&event_list) && children == 0) { /* we are idle */ timeout = -1; @@ -1255,8 +1241,20 @@ int main(int argc, char *argv[]) cg_kill(SYSTEMD_CGROUP_CONTROLLER, udev_cgroup, SIGKILL, false, true, NULL); } else { /* kill idle or hanging workers */ - timeout = 3 * 1000; + timeout = 3 * MSEC_PER_SEC; } + + /* tell settle that we are busy or idle */ + if (!udev_list_node_is_empty(&event_list)) { + int fd; + + fd = open("/run/udev/queue", O_WRONLY|O_CREAT|O_CLOEXEC|O_TRUNC|O_NOFOLLOW, 0444); + if (fd >= 0) + close(fd); + } else { + unlink("/run/udev/queue"); + } + fdcount = epoll_wait(fd_ep, ev, ELEMENTSOF(ev), timeout); if (fdcount < 0) continue; @@ -1283,18 +1281,18 @@ int main(int argc, char *argv[]) if (worker->state != WORKER_RUNNING) continue; - if ((now(CLOCK_MONOTONIC) - worker->event_start_usec) > 30 * 1000 * 1000) { + if ((now(CLOCK_MONOTONIC) - worker->event_start_usec) > 30 * USEC_PER_SEC) { log_error("worker [%u] %s timeout; kill it", worker->pid, worker->event ? worker->event->devpath : ""); kill(worker->pid, SIGKILL); worker->state = WORKER_KILLED; + /* drop reference taken for state 'running' */ worker_unref(worker); if (worker->event) { - log_error("seq %llu '%s' killed", - udev_device_get_seqnum(worker->event->dev), worker->event->devpath); + log_error("seq %llu '%s' killed", udev_device_get_seqnum(worker->event->dev), worker->event->devpath); worker->event->exitcode = -64; - event_queue_delete(worker->event, true); + event_queue_delete(worker->event); worker->event = NULL; } } @@ -1317,7 +1315,7 @@ int main(int argc, char *argv[]) } /* check for changed config, every 3 seconds at most */ - if ((now(CLOCK_MONOTONIC) - last_usec) > 3 * 1000 * 1000) { + if ((now(CLOCK_MONOTONIC) - last_usec) > 3 * USEC_PER_SEC) { if (udev_rules_check_timestamp(rules)) reload = true; if (udev_builtin_validate(udev)) @@ -1390,8 +1388,8 @@ int main(int argc, char *argv[]) rc = EXIT_SUCCESS; exit: - udev_queue_export_cleanup(udev_queue_export); udev_ctrl_cleanup(udev_ctrl); + unlink("/run/udev/queue"); exit_daemonize: if (fd_ep >= 0) close(fd_ep); @@ -1406,7 +1404,6 @@ exit_daemonize: if (worker_watch[WRITE_END] >= 0) close(worker_watch[WRITE_END]); udev_monitor_unref(monitor); - udev_queue_export_unref(udev_queue_export); udev_ctrl_connection_unref(ctrl_conn); udev_ctrl_unref(udev_ctrl); label_finish(); -- cgit v1.2.3-54-g00ecf