X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=src%2Fudev%2Fudevd.c;h=e72c5b231e004aec76e9b16461acb8af6dfea094;hp=6100d7d57a3d7e0409eb3eb4a64958ed9b33f863;hb=ad6e5b348fa88f44d6cbfe7aabda7612a1d0463f;hpb=f3a740a5dae792fb6b2d411022ce8c29ced1c3f1

diff --git a/src/udev/udevd.c b/src/udev/udevd.c
index 6100d7d57..e72c5b231 100644
--- a/src/udev/udevd.c
+++ b/src/udev/udevd.c
@@ -38,6 +38,7 @@
 #include <sys/un.h>
 #include <sys/signalfd.h>
 #include <sys/epoll.h>
+#include <sys/mount.h>
 #include <sys/poll.h>
 #include <sys/wait.h>
 #include <sys/stat.h>
@@ -56,8 +57,7 @@ static bool debug;
 
 void udev_main_log(struct udev *udev, int priority,
                    const char *file, int line, const char *fn,
-                   const char *format, va_list args)
-{
+                   const char *format, va_list args) {
         log_metav(priority, file, line, fn, format, args);
 }
 
@@ -73,6 +73,7 @@ static bool reload;
 static int children;
 static int children_max;
 static int exec_delay;
+static usec_t event_timeout_usec = 60 * USEC_PER_SEC;
 static sigset_t sigmask_orig;
 static UDEV_LIST(event_list);
 static UDEV_LIST(worker_list);
@@ -99,13 +100,9 @@ struct event {
         dev_t devnum;
         int ifindex;
         bool is_block;
-#ifdef HAVE_FIRMWARE
-        bool nodelay;
-#endif
 };
 
-static inline struct event *node_to_event(struct udev_list_node *node)
-{
+static inline struct event *node_to_event(struct udev_list_node *node) {
         return container_of(node, struct event, node);
 }
 
@@ -135,34 +132,29 @@ struct worker_message {
         int exitcode;
 };
 
-static inline struct worker *node_to_worker(struct udev_list_node *node)
-{
+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)
-{
+static void event_queue_delete(struct event *event) {
         udev_list_node_remove(&event->node);
         udev_device_unref(event->dev);
         free(event);
 }
 
-static struct worker *worker_ref(struct worker *worker)
-{
+static struct worker *worker_ref(struct worker *worker) {
         worker->refcount++;
         return worker;
 }
 
-static void worker_cleanup(struct worker *worker)
-{
+static void worker_cleanup(struct worker *worker) {
         udev_list_node_remove(&worker->node);
         udev_monitor_unref(worker->monitor);
         children--;
         free(worker);
 }
 
-static void worker_unref(struct worker *worker)
-{
+static void worker_unref(struct worker *worker) {
         worker->refcount--;
         if (worker->refcount > 0)
                 return;
@@ -170,8 +162,7 @@ static void worker_unref(struct worker *worker)
         worker_cleanup(worker);
 }
 
-static void worker_list_cleanup(struct udev *udev)
-{
+static void worker_list_cleanup(struct udev *udev) {
         struct udev_list_node *loop, *tmp;
 
         udev_list_node_foreach_safe(loop, tmp, &worker_list) {
@@ -181,8 +172,7 @@ static void worker_list_cleanup(struct udev *udev)
         }
 }
 
-static void worker_new(struct event *event)
-{
+static void worker_new(struct event *event) {
         struct udev *udev = event->udev;
         struct worker *worker;
         struct udev_monitor *worker_monitor;
@@ -284,26 +274,17 @@ static void worker_new(struct event *event)
                                 udev_event->exec_delay = exec_delay;
 
                         /*
-                         * Take a "read lock" on the device node; this establishes
+                         * Take a shared lock on the device node; this establishes
                          * a concept of device "ownership" to serialize device
-                         * access. External processes holding a "write lock" will
+                         * 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 will block until
+                         * acquired the lock, the external process can block until
                          * udev has finished its event handling.
                          */
-
-                        /*
-                         * <kabi_> since we make check - device seems unused - we try
-                         *         ioctl to deactivate - and device is found to be opened
-                         * <kay> sure, you try to take a write lock
-                         * <kay> if you get it udev is out
-                         * <kay> if you can't get it, udev is busy
-                         * <kabi_> we cannot deactivate openned device  (as it is in-use)
-                         * <kay> maybe we should just exclude dm from that thing entirely
-                         * <kabi_> IMHO this sounds like a good plan for this moment
-                         */
-                        if (streq_ptr("block", udev_device_get_subsystem(dev)) &&
-                            !startswith("dm-", udev_device_get_sysname(dev))) {
+                        if (!streq_ptr(udev_device_get_action(dev), "remove") &&
+                            streq_ptr("block", udev_device_get_subsystem(dev)) &&
+                            !startswith(udev_device_get_sysname(dev), "dm-") &&
+                            !startswith(udev_device_get_sysname(dev), "md")) {
                                 struct udev_device *d = dev;
 
                                 if (streq_ptr("partition", udev_device_get_devtype(d)))
@@ -321,9 +302,9 @@ static void worker_new(struct event *event)
                         }
 
                         /* apply rules, create node, symlinks */
-                        udev_event_execute_rules(udev_event, rules, &sigmask_orig);
+                        udev_event_execute_rules(udev_event, event_timeout_usec, rules, &sigmask_orig);
 
-                        udev_event_execute_run(udev_event, &sigmask_orig);
+                        udev_event_execute_run(udev_event, event_timeout_usec, &sigmask_orig);
 
                         /* apply/restore inotify watch */
                         if (udev_event->inotify_watch) {
@@ -423,8 +404,7 @@ out:
         }
 }
 
-static void event_run(struct event *event)
-{
+static void event_run(struct event *event) {
         struct udev_list_node *loop;
 
         udev_list_node_foreach(loop, &worker_list) {
@@ -459,8 +439,7 @@ static void event_run(struct event *event)
         worker_new(event);
 }
 
-static int event_queue_insert(struct udev_device *dev)
-{
+static int event_queue_insert(struct udev_device *dev) {
         struct event *event;
 
         event = new0(struct event, 1);
@@ -476,10 +455,6 @@ static int event_queue_insert(struct udev_device *dev)
         event->devnum = udev_device_get_devnum(dev);
         event->is_block = streq("block", udev_device_get_subsystem(dev));
         event->ifindex = udev_device_get_ifindex(dev);
-#ifdef HAVE_FIRMWARE
-        if (streq(udev_device_get_subsystem(dev), "firmware"))
-                event->nodelay = true;
-#endif
 
         log_debug("seq %llu queued, '%s' '%s'", udev_device_get_seqnum(dev),
              udev_device_get_action(dev), udev_device_get_subsystem(dev));
@@ -489,8 +464,7 @@ static int event_queue_insert(struct udev_device *dev)
         return 0;
 }
 
-static void worker_kill(struct udev *udev)
-{
+static void worker_kill(struct udev *udev) {
         struct udev_list_node *loop;
 
         udev_list_node_foreach(loop, &worker_list) {
@@ -505,8 +479,7 @@ static void worker_kill(struct udev *udev)
 }
 
 /* lookup event for identical, parent, child device */
-static bool is_devpath_busy(struct event *event)
-{
+static bool is_devpath_busy(struct event *event) {
         struct udev_list_node *loop;
         size_t common;
 
@@ -558,12 +531,6 @@ static bool is_devpath_busy(struct event *event)
                         return true;
                 }
 
-#ifdef HAVE_FIRMWARE
-                /* allow to bypass the dependency tracking */
-                if (event->nodelay)
-                        continue;
-#endif
-
                 /* parent device event found */
                 if (event->devpath[common] == '/') {
                         event->delaying_seqnum = loop_event->seqnum;
@@ -583,8 +550,7 @@ static bool is_devpath_busy(struct event *event)
         return false;
 }
 
-static void event_queue_start(struct udev *udev)
-{
+static void event_queue_start(struct udev *udev) {
         struct udev_list_node *loop;
 
         udev_list_node_foreach(loop, &event_list) {
@@ -601,8 +567,7 @@ static void event_queue_start(struct udev *udev)
         }
 }
 
-static void event_queue_cleanup(struct udev *udev, enum event_state match_type)
-{
+static void event_queue_cleanup(struct udev *udev, enum event_state match_type) {
         struct udev_list_node *loop, *tmp;
 
         udev_list_node_foreach_safe(loop, tmp, &event_list) {
@@ -615,8 +580,7 @@ static void event_queue_cleanup(struct udev *udev, enum event_state match_type)
         }
 }
 
-static void worker_returned(int fd_worker)
-{
+static void worker_returned(int fd_worker) {
         for (;;) {
                 struct worker_message msg;
                 ssize_t size;
@@ -648,8 +612,7 @@ static void worker_returned(int fd_worker)
 }
 
 /* receive the udevd message from userspace */
-static struct udev_ctrl_connection *handle_ctrl_msg(struct udev_ctrl *uctrl)
-{
+static struct udev_ctrl_connection *handle_ctrl_msg(struct udev_ctrl *uctrl) {
         struct udev *udev = udev_ctrl_get_udev(uctrl);
         struct udev_ctrl_connection *ctrl_conn;
         struct udev_ctrl_msg *ctrl_msg = NULL;
@@ -738,17 +701,34 @@ static int synthesize_change(struct udev_device *dev) {
         char filename[UTIL_PATH_SIZE];
         int r;
 
-        log_debug("device %s closed, synthesising 'change'", udev_device_get_devnode(dev));
-        strscpyl(filename, sizeof(filename), udev_device_get_syspath(dev), "/uevent", NULL);
-        write_string_file(filename, "change");
-
-        /* for disks devices, re-trigger all partitions too */
         if (streq_ptr("block", udev_device_get_subsystem(dev)) &&
-            streq_ptr("disk", udev_device_get_devtype(dev))) {
+            streq_ptr("disk", udev_device_get_devtype(dev)) &&
+            !startswith(udev_device_get_sysname(dev), "dm-")) {
+                bool part_table_read = false;
+                bool has_partitions = false;
+                int fd;
                 struct udev *udev = udev_device_get_udev(dev);
                 _cleanup_udev_enumerate_unref_ struct udev_enumerate *e = NULL;
                 struct udev_list_entry *item;
 
+                /*
+                 * Try to re-read the partition table. This only succeeds if
+                 * none of the devices is busy. The kernel returns 0 if no
+                 * partition table is found, and we will not get an event for
+                 * the disk.
+                 */
+                fd = open(udev_device_get_devnode(dev), O_RDONLY|O_CLOEXEC|O_NOFOLLOW|O_NONBLOCK);
+                if (fd >= 0) {
+                        r = flock(fd, LOCK_EX|LOCK_NB);
+                        if (r >= 0)
+                                r = ioctl(fd, BLKRRPART, 0);
+
+                        close(fd);
+                        if (r >= 0)
+                                part_table_read = true;
+                }
+
+                /* search for partitions */
                 e = udev_enumerate_new(udev);
                 if (!e)
                         return -ENOMEM;
@@ -762,6 +742,39 @@ static int synthesize_change(struct udev_device *dev) {
                         return r;
 
                 r = udev_enumerate_scan_devices(e);
+                if (r < 0)
+                        return r;
+
+                udev_list_entry_foreach(item, udev_enumerate_get_list_entry(e)) {
+                        _cleanup_udev_device_unref_ struct udev_device *d = NULL;
+
+                        d = udev_device_new_from_syspath(udev, udev_list_entry_get_name(item));
+                        if (!d)
+                                continue;
+
+                        if (!streq_ptr("partition", udev_device_get_devtype(d)))
+                                continue;
+
+                        has_partitions = true;
+                        break;
+                }
+
+                /*
+                 * We have partitions and re-read the table, the kernel already sent
+                 * out a "change" event for the disk, and "remove/add" for all
+                 * partitions.
+                 */
+                if (part_table_read && has_partitions)
+                        return 0;
+
+                /*
+                 * We have partitions but re-reading the partition table did not
+                 * work, synthesize "change" for the disk and all partitions.
+                 */
+                log_debug("device %s closed, synthesising 'change'", udev_device_get_devnode(dev));
+                strscpyl(filename, sizeof(filename), udev_device_get_syspath(dev), "/uevent", NULL);
+                write_string_file(filename, "change");
+
                 udev_list_entry_foreach(item, udev_enumerate_get_list_entry(e)) {
                         _cleanup_udev_device_unref_ struct udev_device *d = NULL;
 
@@ -777,13 +790,18 @@ static int synthesize_change(struct udev_device *dev) {
                         strscpyl(filename, sizeof(filename), udev_device_get_syspath(d), "/uevent", NULL);
                         write_string_file(filename, "change");
                 }
+
+                return 0;
         }
 
+        log_debug("device %s closed, synthesising 'change'", udev_device_get_devnode(dev));
+        strscpyl(filename, sizeof(filename), udev_device_get_syspath(dev), "/uevent", NULL);
+        write_string_file(filename, "change");
+
         return 0;
 }
 
-static int handle_inotify(struct udev *udev)
-{
+static int handle_inotify(struct udev *udev) {
         int nbytes, pos;
         char *buf;
         struct inotify_event *ev;
@@ -822,8 +840,7 @@ static int handle_inotify(struct udev *udev)
         return 0;
 }
 
-static void handle_signal(struct udev *udev, int signo)
-{
+static void handle_signal(struct udev *udev, int signo) {
         switch (signo) {
         case SIGINT:
         case SIGTERM:
@@ -883,8 +900,7 @@ static void handle_signal(struct udev *udev, int signo)
         }
 }
 
-static int systemd_fds(struct udev *udev, int *rctrl, int *rnetlink)
-{
+static int systemd_fds(struct udev *udev, int *rctrl, int *rnetlink) {
         int ctrl = -1, netlink = -1;
         int fd, n;
 
@@ -925,10 +941,9 @@ static int systemd_fds(struct udev *udev, int *rctrl, int *rnetlink)
  *   udev.children-max=<number of workers>  events are fully serialized if set to 1
  *   udev.exec-delay=<number of seconds>    delay execution of every executed program
  */
-static void kernel_cmdline_options(struct udev *udev)
-{
+static void kernel_cmdline_options(struct udev *udev) {
         _cleanup_free_ char *line = NULL;
-        char *w, *state;
+        const char *word, *state;
         size_t l;
         int r;
 
@@ -938,10 +953,10 @@ static void kernel_cmdline_options(struct udev *udev)
         if (r <= 0)
                 return;
 
-        FOREACH_WORD_QUOTED(w, l, line, state) {
+        FOREACH_WORD_QUOTED(word, l, line, state) {
                 char *s, *opt;
 
-                s = strndup(w, l);
+                s = strndup(word, l);
                 if (!s)
                         break;
 
@@ -961,14 +976,15 @@ static void kernel_cmdline_options(struct udev *udev)
                         children_max = strtoul(opt + 18, NULL, 0);
                 } else if (startswith(opt, "udev.exec-delay=")) {
                         exec_delay = strtoul(opt + 16, NULL, 0);
+                } else if (startswith(opt, "udev.event-timeout=")) {
+                        event_timeout_usec = strtoul(opt + 16, NULL, 0) * USEC_PER_SEC;
                 }
 
                 free(s);
         }
 }
 
-int main(int argc, char *argv[])
-{
+int main(int argc, char *argv[]) {
         struct udev *udev;
         sigset_t mask;
         int daemonize = false;
@@ -978,6 +994,7 @@ int main(int argc, char *argv[])
                 { "debug", no_argument, NULL, 'D' },
                 { "children-max", required_argument, NULL, 'c' },
                 { "exec-delay", required_argument, NULL, 'e' },
+                { "event-timeout", required_argument, NULL, 't' },
                 { "resolve-names", required_argument, NULL, 'N' },
                 { "help", no_argument, NULL, 'h' },
                 { "version", no_argument, NULL, 'V' },
@@ -1021,6 +1038,9 @@ int main(int argc, char *argv[])
                 case 'e':
                         exec_delay = strtoul(optarg, NULL, 0);
                         break;
+                case 't':
+                        event_timeout_usec = strtoul(optarg, NULL, 0) * USEC_PER_SEC;
+                        break;
                 case 'D':
                         debug = true;
                         log_set_max_level(LOG_DEBUG);
@@ -1045,6 +1065,7 @@ int main(int argc, char *argv[])
                                "  --debug\n"
                                "  --children-max=<maximum number of workers>\n"
                                "  --exec-delay=<seconds to wait before executing RUN=>\n"
+                               "  --event-timeout=<seconds to wait before terminating an event>\n"
                                "  --resolve-names=early|late|never\n"
                                "  --version\n"
                                "  --help\n"
@@ -1358,20 +1379,17 @@ int main(int argc, char *argv[])
                                 if (worker->state != WORKER_RUNNING)
                                         continue;
 
-                                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 : "<idle>");
+                                if ((now(CLOCK_MONOTONIC) - worker->event_start_usec) > event_timeout_usec) {
+                                        log_error("worker [%u] %s timeout; kill it", worker->pid, 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);
-                                                worker->event->exitcode = -64;
-                                                event_queue_delete(worker->event);
-                                                worker->event = NULL;
-                                        }
+                                        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);
+                                        worker->event = NULL;
                                 }
                         }