X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?a=blobdiff_plain;f=src%2Fcore%2Fmount.c;h=f8731bb8b979cb955fb07165b429ed3e798fc846;hb=821d4b6e068b2afaad94d43db22171c34a30400e;hp=36375f65bcde4d88790a82d4e9d144e4dd60dfca;hpb=79008bddf679a5e0900369950eb346c9fa687107;p=elogind.git diff --git a/src/core/mount.c b/src/core/mount.c index 36375f65b..f8731bb8b 100644 --- a/src/core/mount.c +++ b/src/core/mount.c @@ -24,6 +24,8 @@ #include #include #include +#include +#include #include "manager.h" #include "unit.h" @@ -39,10 +41,15 @@ #include "unit-name.h" #include "dbus-mount.h" #include "special.h" -#include "bus-errors.h" +#include "bus-common-errors.h" #include "exit-status.h" #include "def.h" +#define RETRY_UMOUNT_MAX 32 + +DEFINE_TRIVIAL_CLEANUP_FUNC(struct libmnt_table*, mnt_free_table); +DEFINE_TRIVIAL_CLEANUP_FUNC(struct libmnt_iter*, mnt_free_iter); + static const UnitActiveState state_translation_table[_MOUNT_STATE_MAX] = { [MOUNT_DEAD] = UNIT_INACTIVE, [MOUNT_MOUNTING] = UNIT_ACTIVATING, @@ -62,19 +69,23 @@ static const UnitActiveState state_translation_table[_MOUNT_STATE_MAX] = { static int mount_dispatch_timer(sd_event_source *source, usec_t usec, void *userdata); static int mount_dispatch_io(sd_event_source *source, int fd, uint32_t revents, void *userdata); -static bool mount_is_network(MountParameters *p) { - assert(p); - - if (mount_test_option(p->options, "_netdev")) +static bool mount_needs_network(const char *options, const char *fstype) { + if (mount_test_option(options, "_netdev")) return true; - if (p->fstype && fstype_is_network(p->fstype)) + if (fstype && fstype_is_network(fstype)) return true; return false; } -static bool mount_is_bind(MountParameters *p) { +static bool mount_is_network(const MountParameters *p) { + assert(p); + + return mount_needs_network(p->options, p->fstype); +} + +static bool mount_is_bind(const MountParameters *p) { assert(p); if (mount_test_option(p->options, "bind")) @@ -92,13 +103,13 @@ static bool mount_is_bind(MountParameters *p) { return false; } -static bool mount_is_auto(MountParameters *p) { +static bool mount_is_auto(const MountParameters *p) { assert(p); return !mount_test_option(p->options, "noauto"); } -static bool needs_quota(MountParameters *p) { +static bool needs_quota(const MountParameters *p) { assert(p); if (mount_is_network(p)) @@ -823,12 +834,12 @@ void warn_if_dir_nonempty(const char *unit, const char* where) { if (r > 0) return; else if (r == 0) - log_unit_struct(LOG_NOTICE, - unit, - "MESSAGE=%s: Directory %s to mount over is not empty, mounting anyway.", - unit, where, + log_unit_struct(unit, + LOG_NOTICE, + LOG_MESSAGE_ID(SD_MESSAGE_OVERMOUNTING), + LOG_MESSAGE("%s: Directory %s to mount over is not empty, mounting anyway.", + unit, where), "WHERE=%s", where, - MESSAGE_ID(SD_MESSAGE_OVERMOUNTING), NULL); else log_unit_warning(unit, @@ -840,12 +851,12 @@ static int fail_if_symlink(const char *unit, const char* where) { assert(where); if (is_symlink(where) > 0) { - log_unit_struct(LOG_WARNING, - unit, - "MESSAGE=%s: Mount on symlink %s not allowed.", - unit, where, + log_unit_struct(unit, + LOG_ERR, + LOG_MESSAGE_ID(SD_MESSAGE_OVERMOUNTING), + LOG_MESSAGE("%s: Mount on symlink %s not allowed.", + unit, where), "WHERE=%s", where, - MESSAGE_ID(SD_MESSAGE_OVERMOUNTING), NULL); return -ELOOP; @@ -858,20 +869,28 @@ static void mount_enter_unmounting(Mount *m) { assert(m); + /* Start counting our attempts */ + if (!IN_SET(m->state, + MOUNT_UNMOUNTING, + MOUNT_UNMOUNTING_SIGTERM, + MOUNT_UNMOUNTING_SIGKILL)) + m->n_retry_umount = 0; + m->control_command_id = MOUNT_EXEC_UNMOUNT; m->control_command = m->exec_command + MOUNT_EXEC_UNMOUNT; - if ((r = exec_command_set( - m->control_command, + r = exec_command_set(m->control_command, "/bin/umount", "-n", m->where, - NULL)) < 0) + NULL); + if (r < 0) goto fail; mount_unwatch_control_pid(m); - if ((r = mount_spawn(m, m->control_command, &m->control_pid)) < 0) + r = mount_spawn(m, m->control_command, &m->control_pid); + if (r < 0) goto fail; mount_set_state(m, MOUNT_UNMOUNTING); @@ -1230,9 +1249,31 @@ static void mount_sigchld_event(Unit *u, pid_t pid, int code, int status) { case MOUNT_UNMOUNTING_SIGKILL: case MOUNT_UNMOUNTING_SIGTERM: - if (f == MOUNT_SUCCESS) - mount_enter_dead(m, f); - else if (m->from_proc_self_mountinfo) + if (f == MOUNT_SUCCESS) { + + if (m->from_proc_self_mountinfo) { + + /* Still a mount point? If so, let's + * try again. Most likely there were + * multiple mount points stacked on + * top of each other. Note that due to + * the io event priority logic we can + * be sure the new mountinfo is loaded + * before we process the SIGCHLD for + * the mount command. */ + + if (m->n_retry_umount < RETRY_UMOUNT_MAX) { + log_unit_debug(u->id, "%s: mount still present, trying again.", u->id); + m->n_retry_umount++; + mount_enter_unmounting(m); + } else { + log_unit_debug(u->id, "%s: mount still present after %u attempts to unmount, giving up.", u->id, m->n_retry_umount); + mount_enter_mounted(m, f); + } + } else + mount_enter_dead(m, f); + + } else if (m->from_proc_self_mountinfo) mount_enter_mounted(m, f); else mount_enter_dead(m, f); @@ -1406,12 +1447,10 @@ static int mount_add_one( goto fail; } - if (m->running_as == SYSTEMD_SYSTEM) { const char* target; - target = fstype_is_network(fstype) ? SPECIAL_REMOTE_FS_TARGET : SPECIAL_LOCAL_FS_TARGET; - + target = mount_needs_network(options, fstype) ? SPECIAL_REMOTE_FS_TARGET : SPECIAL_LOCAL_FS_TARGET; r = unit_add_dependency_by_name(u, UNIT_BEFORE, target, NULL, true); if (r < 0) goto fail; @@ -1436,6 +1475,15 @@ static int mount_add_one( } } + if (m->running_as == SYSTEMD_SYSTEM && + mount_needs_network(options, fstype)) { + /* _netdev option may have shown up late, or on a + * remount. Add remote-fs dependencies, even though + * local-fs ones may already be there. */ + unit_add_dependency_by_name(u, UNIT_BEFORE, SPECIAL_REMOTE_FS_TARGET, NULL, true); + load_extras = true; + } + if (u->load_state == UNIT_NOT_FOUND) { u->load_state = UNIT_LOADED; u->load_error = 0; @@ -1501,55 +1549,46 @@ fail: } static int mount_load_proc_self_mountinfo(Manager *m, bool set_flags) { + _cleanup_(mnt_free_tablep) struct libmnt_table *tb = NULL; + _cleanup_(mnt_free_iterp) struct libmnt_iter *itr = NULL; + struct libmnt_fs *fs; int r = 0; - unsigned i; assert(m); - rewind(m->proc_self_mountinfo); + tb = mnt_new_table(); + itr = mnt_new_iter(MNT_ITER_FORWARD); + if (!tb || !itr) + return log_oom(); - for (i = 1;; i++) { - _cleanup_free_ char *device = NULL, *path = NULL, *options = NULL, *options2 = NULL, *fstype = NULL, *d = NULL, *p = NULL, *o = NULL; + r = mnt_table_parse_mtab(tb, NULL); + if (r < 0) + return r; + + r = 0; + for (;;) { + const char *device, *path, *options, *fstype; + _cleanup_free_ const char *d = NULL, *p = NULL; int k; - k = fscanf(m->proc_self_mountinfo, - "%*s " /* (1) mount id */ - "%*s " /* (2) parent id */ - "%*s " /* (3) major:minor */ - "%*s " /* (4) root */ - "%ms " /* (5) mount point */ - "%ms" /* (6) mount options */ - "%*[^-]" /* (7) optional fields */ - "- " /* (8) separator */ - "%ms " /* (9) file system type */ - "%ms" /* (10) mount source */ - "%ms" /* (11) mount options 2 */ - "%*[^\n]", /* some rubbish at the end */ - &path, - &options, - &fstype, - &device, - &options2); - - if (k == EOF) + k = mnt_table_next_fs(tb, itr, &fs); + if (k == 1) break; + else if (k < 0) + return log_error_errno(k, "Failed to get next entry from /etc/fstab: %m"); - if (k != 5) { - log_warning("Failed to parse /proc/self/mountinfo:%u.", i); - continue; - } - - o = strjoin(options, ",", options2, NULL); - if (!o) - return log_oom(); + device = mnt_fs_get_source(fs); + path = mnt_fs_get_target(fs); + options = mnt_fs_get_options(fs); + fstype = mnt_fs_get_fstype(fs); d = cunescape(device); p = cunescape(path); if (!d || !p) return log_oom(); - k = mount_add_one(m, d, p, o, fstype, set_flags); - if (k < 0) + k = mount_add_one(m, d, p, options, fstype, set_flags); + if (r == 0 && k < 0) r = k; } @@ -1560,11 +1599,13 @@ static void mount_shutdown(Manager *m) { assert(m); m->mount_event_source = sd_event_source_unref(m->mount_event_source); + m->mount_utab_event_source = sd_event_source_unref(m->mount_utab_event_source); if (m->proc_self_mountinfo) { fclose(m->proc_self_mountinfo); m->proc_self_mountinfo = NULL; } + m->utab_inotify_fd = safe_close(m->utab_inotify_fd); } static int mount_get_timeout(Unit *u, uint64_t *timeout) { @@ -1585,6 +1626,8 @@ static int mount_enumerate(Manager *m) { int r; assert(m); + mnt_init_debug(0); + if (!m->proc_self_mountinfo) { m->proc_self_mountinfo = fopen("/proc/self/mountinfo", "re"); if (!m->proc_self_mountinfo) @@ -1602,6 +1645,30 @@ static int mount_enumerate(Manager *m) { goto fail; } + if (m->utab_inotify_fd < 0) { + m->utab_inotify_fd = inotify_init1(IN_NONBLOCK|IN_CLOEXEC); + if (m->utab_inotify_fd < 0) { + r = -errno; + goto fail; + } + + (void) mkdir_p_label("/run/mount", 0755); + + r = inotify_add_watch(m->utab_inotify_fd, "/run/mount", IN_MOVED_TO); + if (r < 0) { + r = -errno; + goto fail; + } + + r = sd_event_add_io(m->event, &m->mount_utab_event_source, m->utab_inotify_fd, EPOLLIN, mount_dispatch_io, m); + if (r < 0) + goto fail; + + r = sd_event_source_set_priority(m->mount_utab_event_source, -10); + if (r < 0) + goto fail; + } + r = mount_load_proc_self_mountinfo(m, false); if (r < 0) goto fail; @@ -1619,15 +1686,52 @@ static int mount_dispatch_io(sd_event_source *source, int fd, uint32_t revents, int r; assert(m); - assert(revents & EPOLLPRI); + assert(revents & (EPOLLPRI | EPOLLIN)); /* The manager calls this for every fd event happening on the * /proc/self/mountinfo file, which informs us about mounting - * table changes */ + * table changes, and for /run/mount events which we watch + * for mount options. */ + + if (fd == m->utab_inotify_fd) { + bool rescan = false; + + /* FIXME: We *really* need to replace this with + * libmount's own API for this, we should not hardcode + * internal behaviour of libmount here. */ + + for (;;) { + uint8_t buffer[INOTIFY_EVENT_MAX] _alignas_(struct inotify_event); + struct inotify_event *e; + ssize_t l; + + l = read(fd, buffer, sizeof(buffer)); + if (l < 0) { + if (errno == EAGAIN || errno == EINTR) + break; + + log_error_errno(errno, "Failed to read utab inotify: %m"); + break; + } + + FOREACH_INOTIFY_EVENT(e, buffer, l) { + /* Only care about changes to utab, + * but we have to monitor the + * directory to reliably get + * notifications about when utab is + * replaced using rename(2) */ + if ((e->mask & IN_Q_OVERFLOW) || streq(e->name, "utab")) + rescan = true; + } + } + + if (!rescan) + return 0; + } r = mount_load_proc_self_mountinfo(m, true); if (r < 0) { - log_error("Failed to reread /proc/self/mountinfo: %s", strerror(-r)); + log_error_errno(r, "Failed to reread /proc/self/mountinfo: %m"); /* Reset flags, just in case, for later calls */ LIST_FOREACH(units_by_type, u, m->units_by_type[UNIT_MOUNT]) {