| /* SPDX-License-Identifier: LGPL-2.1+ */ |
| |
| #include <errno.h> |
| #include <sys/epoll.h> |
| |
| #include "libudev.h" |
| |
| #include "alloc-util.h" |
| #include "bus-error.h" |
| #include "dbus-device.h" |
| #include "device.h" |
| #include "log.h" |
| #include "parse-util.h" |
| #include "path-util.h" |
| #include "stat-util.h" |
| #include "string-util.h" |
| #include "swap.h" |
| #include "udev-util.h" |
| #include "unit-name.h" |
| #include "unit.h" |
| |
| static const UnitActiveState state_translation_table[_DEVICE_STATE_MAX] = { |
| [DEVICE_DEAD] = UNIT_INACTIVE, |
| [DEVICE_TENTATIVE] = UNIT_ACTIVATING, |
| [DEVICE_PLUGGED] = UNIT_ACTIVE, |
| }; |
| |
| static int device_dispatch_io(sd_event_source *source, int fd, uint32_t revents, void *userdata); |
| static void device_update_found_one(Device *d, DeviceFound found, DeviceFound mask); |
| |
| static void device_unset_sysfs(Device *d) { |
| Hashmap *devices; |
| Device *first; |
| |
| assert(d); |
| |
| if (!d->sysfs) |
| return; |
| |
| /* Remove this unit from the chain of devices which share the |
| * same sysfs path. */ |
| devices = UNIT(d)->manager->devices_by_sysfs; |
| first = hashmap_get(devices, d->sysfs); |
| LIST_REMOVE(same_sysfs, first, d); |
| |
| if (first) |
| hashmap_remove_and_replace(devices, d->sysfs, first->sysfs, first); |
| else |
| hashmap_remove(devices, d->sysfs); |
| |
| d->sysfs = mfree(d->sysfs); |
| } |
| |
| static int device_set_sysfs(Device *d, const char *sysfs) { |
| _cleanup_free_ char *copy = NULL; |
| Device *first; |
| int r; |
| |
| assert(d); |
| |
| if (streq_ptr(d->sysfs, sysfs)) |
| return 0; |
| |
| r = hashmap_ensure_allocated(&UNIT(d)->manager->devices_by_sysfs, &path_hash_ops); |
| if (r < 0) |
| return r; |
| |
| copy = strdup(sysfs); |
| if (!copy) |
| return -ENOMEM; |
| |
| device_unset_sysfs(d); |
| |
| first = hashmap_get(UNIT(d)->manager->devices_by_sysfs, sysfs); |
| LIST_PREPEND(same_sysfs, first, d); |
| |
| r = hashmap_replace(UNIT(d)->manager->devices_by_sysfs, copy, first); |
| if (r < 0) { |
| LIST_REMOVE(same_sysfs, first, d); |
| return r; |
| } |
| |
| d->sysfs = TAKE_PTR(copy); |
| unit_add_to_dbus_queue(UNIT(d)); |
| |
| return 0; |
| } |
| |
| static void device_init(Unit *u) { |
| Device *d = DEVICE(u); |
| |
| assert(d); |
| assert(UNIT(d)->load_state == UNIT_STUB); |
| |
| /* In contrast to all other unit types we timeout jobs waiting |
| * for devices by default. This is because they otherwise wait |
| * indefinitely for plugged in devices, something which cannot |
| * happen for the other units since their operations time out |
| * anyway. */ |
| u->job_running_timeout = u->manager->default_timeout_start_usec; |
| |
| u->ignore_on_isolate = true; |
| |
| d->deserialized_state = _DEVICE_STATE_INVALID; |
| } |
| |
| static void device_done(Unit *u) { |
| Device *d = DEVICE(u); |
| |
| assert(d); |
| |
| device_unset_sysfs(d); |
| d->wants_property = strv_free(d->wants_property); |
| } |
| |
| static void device_set_state(Device *d, DeviceState state) { |
| DeviceState old_state; |
| assert(d); |
| |
| old_state = d->state; |
| d->state = state; |
| |
| if (state == DEVICE_DEAD) |
| device_unset_sysfs(d); |
| |
| if (state != old_state) |
| log_unit_debug(UNIT(d), "Changed %s -> %s", device_state_to_string(old_state), device_state_to_string(state)); |
| |
| unit_notify(UNIT(d), state_translation_table[old_state], state_translation_table[state], 0); |
| } |
| |
| static int device_coldplug(Unit *u) { |
| Device *d = DEVICE(u); |
| |
| assert(d); |
| assert(d->state == DEVICE_DEAD); |
| |
| /* First, let's put the deserialized state and found mask into effect, if we have it. */ |
| |
| if (d->deserialized_state < 0 || |
| (d->deserialized_state == d->state && |
| d->deserialized_found == d->found)) |
| return 0; |
| |
| d->found = d->deserialized_found; |
| device_set_state(d, d->deserialized_state); |
| return 0; |
| } |
| |
| static void device_catchup(Unit *u) { |
| Device *d = DEVICE(u); |
| |
| assert(d); |
| |
| /* Second, let's update the state with the enumerated state if it's different */ |
| if (d->enumerated_found == d->found) |
| return; |
| |
| device_update_found_one(d, d->enumerated_found, DEVICE_FOUND_MASK); |
| } |
| |
| static const struct { |
| DeviceFound flag; |
| const char *name; |
| } device_found_map[] = { |
| { DEVICE_FOUND_UDEV, "found-udev" }, |
| { DEVICE_FOUND_MOUNT, "found-mount" }, |
| { DEVICE_FOUND_SWAP, "found-swap" }, |
| }; |
| |
| static int device_found_to_string_many(DeviceFound flags, char **ret) { |
| _cleanup_free_ char *s = NULL; |
| unsigned i; |
| |
| assert(ret); |
| |
| for (i = 0; i < ELEMENTSOF(device_found_map); i++) { |
| if (!FLAGS_SET(flags, device_found_map[i].flag)) |
| continue; |
| |
| if (!strextend_with_separator(&s, ",", device_found_map[i].name, NULL)) |
| return -ENOMEM; |
| } |
| |
| *ret = TAKE_PTR(s); |
| |
| return 0; |
| } |
| |
| static int device_found_from_string_many(const char *name, DeviceFound *ret) { |
| DeviceFound flags = 0; |
| int r; |
| |
| assert(ret); |
| |
| for (;;) { |
| _cleanup_free_ char *word = NULL; |
| DeviceFound f = 0; |
| unsigned i; |
| |
| r = extract_first_word(&name, &word, ",", 0); |
| if (r < 0) |
| return r; |
| if (r == 0) |
| break; |
| |
| for (i = 0; i < ELEMENTSOF(device_found_map); i++) |
| if (streq(word, device_found_map[i].name)) { |
| f = device_found_map[i].flag; |
| break; |
| } |
| |
| if (f == 0) |
| return -EINVAL; |
| |
| flags |= f; |
| } |
| |
| *ret = flags; |
| return 0; |
| } |
| |
| static int device_serialize(Unit *u, FILE *f, FDSet *fds) { |
| _cleanup_free_ char *s = NULL; |
| Device *d = DEVICE(u); |
| |
| assert(u); |
| assert(f); |
| assert(fds); |
| |
| unit_serialize_item(u, f, "state", device_state_to_string(d->state)); |
| |
| if (device_found_to_string_many(d->found, &s) >= 0) |
| unit_serialize_item(u, f, "found", s); |
| |
| return 0; |
| } |
| |
| static int device_deserialize_item(Unit *u, const char *key, const char *value, FDSet *fds) { |
| Device *d = DEVICE(u); |
| int r; |
| |
| assert(u); |
| assert(key); |
| assert(value); |
| assert(fds); |
| |
| if (streq(key, "state")) { |
| DeviceState state; |
| |
| state = device_state_from_string(value); |
| if (state < 0) |
| log_unit_debug(u, "Failed to parse state value, ignoring: %s", value); |
| else |
| d->deserialized_state = state; |
| |
| } else if (streq(key, "found")) { |
| r = device_found_from_string_many(value, &d->deserialized_found); |
| if (r < 0) |
| log_unit_debug_errno(u, r, "Failed to parse found value, ignoring: %s", value); |
| |
| } else |
| log_unit_debug(u, "Unknown serialization key: %s", key); |
| |
| return 0; |
| } |
| |
| static void device_dump(Unit *u, FILE *f, const char *prefix) { |
| Device *d = DEVICE(u); |
| _cleanup_free_ char *s = NULL; |
| |
| assert(d); |
| |
| (void) device_found_to_string_many(d->found, &s); |
| |
| fprintf(f, |
| "%sDevice State: %s\n" |
| "%sSysfs Path: %s\n" |
| "%sFound: %s\n", |
| prefix, device_state_to_string(d->state), |
| prefix, strna(d->sysfs), |
| prefix, strna(s)); |
| |
| if (!strv_isempty(d->wants_property)) { |
| char **i; |
| |
| STRV_FOREACH(i, d->wants_property) |
| fprintf(f, "%sudev SYSTEMD_WANTS: %s\n", |
| prefix, *i); |
| } |
| } |
| |
| _pure_ static UnitActiveState device_active_state(Unit *u) { |
| assert(u); |
| |
| return state_translation_table[DEVICE(u)->state]; |
| } |
| |
| _pure_ static const char *device_sub_state_to_string(Unit *u) { |
| assert(u); |
| |
| return device_state_to_string(DEVICE(u)->state); |
| } |
| |
| static int device_update_description(Unit *u, struct udev_device *dev, const char *path) { |
| const char *model; |
| int r; |
| |
| assert(u); |
| assert(dev); |
| assert(path); |
| |
| model = udev_device_get_property_value(dev, "ID_MODEL_FROM_DATABASE"); |
| if (!model) |
| model = udev_device_get_property_value(dev, "ID_MODEL"); |
| |
| if (model) { |
| const char *label; |
| |
| /* Try to concatenate the device model string with a label, if there is one */ |
| label = udev_device_get_property_value(dev, "ID_FS_LABEL"); |
| if (!label) |
| label = udev_device_get_property_value(dev, "ID_PART_ENTRY_NAME"); |
| if (!label) |
| label = udev_device_get_property_value(dev, "ID_PART_ENTRY_NUMBER"); |
| |
| if (label) { |
| _cleanup_free_ char *j; |
| |
| j = strjoin(model, " ", label); |
| if (!j) |
| return log_oom(); |
| |
| r = unit_set_description(u, j); |
| } else |
| r = unit_set_description(u, model); |
| } else |
| r = unit_set_description(u, path); |
| if (r < 0) |
| return log_unit_error_errno(u, r, "Failed to set device description: %m"); |
| |
| return 0; |
| } |
| |
| static int device_add_udev_wants(Unit *u, struct udev_device *dev) { |
| _cleanup_strv_free_ char **added = NULL; |
| const char *wants, *property; |
| Device *d = DEVICE(u); |
| int r; |
| |
| assert(d); |
| assert(dev); |
| |
| property = MANAGER_IS_USER(u->manager) ? "SYSTEMD_USER_WANTS" : "SYSTEMD_WANTS"; |
| |
| wants = udev_device_get_property_value(dev, property); |
| if (!wants) |
| return 0; |
| |
| for (;;) { |
| _cleanup_free_ char *word = NULL, *k = NULL; |
| |
| r = extract_first_word(&wants, &word, NULL, EXTRACT_QUOTES); |
| if (r == 0) |
| break; |
| if (r == -ENOMEM) |
| return log_oom(); |
| if (r < 0) |
| return log_unit_error_errno(u, r, "Failed to parse property %s with value %s: %m", property, wants); |
| |
| if (unit_name_is_valid(word, UNIT_NAME_TEMPLATE) && d->sysfs) { |
| _cleanup_free_ char *escaped = NULL; |
| |
| /* If the unit name is specified as template, then automatically fill in the sysfs path of the |
| * device as instance name, properly escaped. */ |
| |
| r = unit_name_path_escape(d->sysfs, &escaped); |
| if (r < 0) |
| return log_unit_error_errno(u, r, "Failed to escape %s: %m", d->sysfs); |
| |
| r = unit_name_replace_instance(word, escaped, &k); |
| if (r < 0) |
| return log_unit_error_errno(u, r, "Failed to build %s instance of template %s: %m", escaped, word); |
| } else { |
| /* If this is not a template, then let's mangle it so, that it becomes a valid unit name. */ |
| |
| r = unit_name_mangle(word, UNIT_NAME_MANGLE_WARN, &k); |
| if (r < 0) |
| return log_unit_error_errno(u, r, "Failed to mangle unit name \"%s\": %m", word); |
| } |
| |
| r = unit_add_dependency_by_name(u, UNIT_WANTS, k, NULL, true, UNIT_DEPENDENCY_UDEV); |
| if (r < 0) |
| return log_unit_error_errno(u, r, "Failed to add Wants= dependency: %m"); |
| |
| r = strv_push(&added, k); |
| if (r < 0) |
| return log_oom(); |
| |
| k = NULL; |
| } |
| |
| if (d->state != DEVICE_DEAD) { |
| char **i; |
| |
| /* So here's a special hack, to compensate for the fact that the udev database's reload cycles are not |
| * synchronized with our own reload cycles: when we detect that the SYSTEMD_WANTS property of a device |
| * changes while the device unit is already up, let's manually trigger any new units listed in it not |
| * seen before. This typically appens during the boot-time switch root transition, as udev devices |
| * will generally already be up in the initrd, but SYSTEMD_WANTS properties get then added through udev |
| * rules only available on the host system, and thus only when the initial udev coldplug trigger runs. |
| * |
| * We do this only if the device has been up already when we parse this, as otherwise the usual |
| * dependency logic that is run from the dead → plugged transition will trigger these deps. */ |
| |
| STRV_FOREACH(i, added) { |
| _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL; |
| |
| if (strv_contains(d->wants_property, *i)) /* Was this unit already listed before? */ |
| continue; |
| |
| r = manager_add_job_by_name(u->manager, JOB_START, *i, JOB_FAIL, &error, NULL); |
| if (r < 0) |
| log_unit_warning_errno(u, r, "Failed to enqueue SYSTEMD_WANTS= job, ignoring: %s", bus_error_message(&error, r)); |
| } |
| } |
| |
| strv_free(d->wants_property); |
| d->wants_property = TAKE_PTR(added); |
| |
| return 0; |
| } |
| |
| static bool device_is_bound_by_mounts(Device *d, struct udev_device *dev) { |
| const char *bound_by; |
| int r; |
| |
| assert(d); |
| assert(dev); |
| |
| bound_by = udev_device_get_property_value(dev, "SYSTEMD_MOUNT_DEVICE_BOUND"); |
| if (bound_by) { |
| r = parse_boolean(bound_by); |
| if (r < 0) |
| log_warning_errno(r, "Failed to parse SYSTEMD_MOUNT_DEVICE_BOUND='%s' udev property of %s, ignoring: %m", bound_by, strna(d->sysfs)); |
| |
| d->bind_mounts = r > 0; |
| } else |
| d->bind_mounts = false; |
| |
| return d->bind_mounts; |
| } |
| |
| static void device_upgrade_mount_deps(Unit *u) { |
| Unit *other; |
| Iterator i; |
| void *v; |
| int r; |
| |
| /* Let's upgrade Requires= to BindsTo= on us. (Used when SYSTEMD_MOUNT_DEVICE_BOUND is set) */ |
| |
| HASHMAP_FOREACH_KEY(v, other, u->dependencies[UNIT_REQUIRED_BY], i) { |
| if (other->type != UNIT_MOUNT) |
| continue; |
| |
| r = unit_add_dependency(other, UNIT_BINDS_TO, u, true, UNIT_DEPENDENCY_UDEV); |
| if (r < 0) |
| log_unit_warning_errno(u, r, "Failed to add BindsTo= dependency between device and mount unit, ignoring: %m"); |
| } |
| } |
| |
| static int device_setup_unit(Manager *m, struct udev_device *dev, const char *path, bool main) { |
| _cleanup_free_ char *e = NULL; |
| const char *sysfs = NULL; |
| Unit *u = NULL; |
| bool delete; |
| int r; |
| |
| assert(m); |
| assert(path); |
| |
| if (dev) { |
| sysfs = udev_device_get_syspath(dev); |
| if (!sysfs) { |
| log_debug("Couldn't get syspath from udev device, ignoring."); |
| return 0; |
| } |
| } |
| |
| r = unit_name_from_path(path, ".device", &e); |
| if (r < 0) |
| return log_error_errno(r, "Failed to generate unit name from device path: %m"); |
| |
| u = manager_get_unit(m, e); |
| if (u) { |
| /* The device unit can still be present even if the device was unplugged: a mount unit can reference it |
| * hence preventing the GC to have garbaged it. That's desired since the device unit may have a |
| * dependency on the mount unit which was added during the loading of the later. When the device is |
| * plugged the sysfs might not be initialized yet, as we serialize the device's state but do not |
| * serialize the sysfs path across reloads/reexecs. Hence, when coming back from a reload/restart we |
| * might have the state valid, but not the sysfs path. Hence, let's filter out conflicting devices, but |
| * let's accept devices in any state with no sysfs path set. */ |
| |
| if (DEVICE(u)->state == DEVICE_PLUGGED && |
| DEVICE(u)->sysfs && |
| sysfs && |
| !path_equal(DEVICE(u)->sysfs, sysfs)) { |
| log_unit_debug(u, "Device %s appeared twice with different sysfs paths %s and %s, ignoring the latter.", |
| e, DEVICE(u)->sysfs, sysfs); |
| return -EEXIST; |
| } |
| |
| delete = false; |
| |
| /* Let's remove all dependencies generated due to udev properties. We'll readd whatever is configured |
| * now below. */ |
| unit_remove_dependencies(u, UNIT_DEPENDENCY_UDEV); |
| } else { |
| delete = true; |
| |
| r = unit_new_for_name(m, sizeof(Device), e, &u); |
| if (r < 0) { |
| log_error_errno(r, "Failed to allocate device unit %s: %m", e); |
| goto fail; |
| } |
| |
| unit_add_to_load_queue(u); |
| } |
| |
| /* If this was created via some dependency and has not actually been seen yet ->sysfs will not be |
| * initialized. Hence initialize it if necessary. */ |
| if (sysfs) { |
| r = device_set_sysfs(DEVICE(u), sysfs); |
| if (r < 0) { |
| log_error_errno(r, "Failed to set sysfs path %s for device unit %s: %m", sysfs, e); |
| goto fail; |
| } |
| |
| (void) device_update_description(u, dev, path); |
| |
| /* The additional systemd udev properties we only interpret for the main object */ |
| if (main) |
| (void) device_add_udev_wants(u, dev); |
| } |
| |
| /* So the user wants the mount units to be bound to the device but a mount unit might has been seen by systemd |
| * before the device appears on its radar. In this case the device unit is partially initialized and includes |
| * the deps on the mount unit but at that time the "bind mounts" flag wasn't not present. Fix this up now. */ |
| if (dev && device_is_bound_by_mounts(DEVICE(u), dev)) |
| device_upgrade_mount_deps(u); |
| |
| return 0; |
| |
| fail: |
| if (delete) |
| unit_free(u); |
| |
| return r; |
| } |
| |
| static int device_process_new(Manager *m, struct udev_device *dev) { |
| const char *sysfs, *dn, *alias; |
| struct udev_list_entry *item = NULL, *first = NULL; |
| int r; |
| |
| assert(m); |
| |
| sysfs = udev_device_get_syspath(dev); |
| if (!sysfs) |
| return 0; |
| |
| /* Add the main unit named after the sysfs path */ |
| r = device_setup_unit(m, dev, sysfs, true); |
| if (r < 0) |
| return r; |
| |
| /* Add an additional unit for the device node */ |
| dn = udev_device_get_devnode(dev); |
| if (dn) |
| (void) device_setup_unit(m, dev, dn, false); |
| |
| /* Add additional units for all symlinks */ |
| first = udev_device_get_devlinks_list_entry(dev); |
| udev_list_entry_foreach(item, first) { |
| const char *p; |
| struct stat st; |
| |
| /* Don't bother with the /dev/block links */ |
| p = udev_list_entry_get_name(item); |
| |
| if (PATH_STARTSWITH_SET(p, "/dev/block/", "/dev/char/")) |
| continue; |
| |
| /* Verify that the symlink in the FS actually belongs |
| * to this device. This is useful to deal with |
| * conflicting devices, e.g. when two disks want the |
| * same /dev/disk/by-label/xxx link because they have |
| * the same label. We want to make sure that the same |
| * device that won the symlink wins in systemd, so we |
| * check the device node major/minor */ |
| if (stat(p, &st) >= 0) |
| if ((!S_ISBLK(st.st_mode) && !S_ISCHR(st.st_mode)) || |
| st.st_rdev != udev_device_get_devnum(dev)) |
| continue; |
| |
| (void) device_setup_unit(m, dev, p, false); |
| } |
| |
| /* Add additional units for all explicitly configured |
| * aliases */ |
| alias = udev_device_get_property_value(dev, "SYSTEMD_ALIAS"); |
| for (;;) { |
| _cleanup_free_ char *word = NULL; |
| |
| r = extract_first_word(&alias, &word, NULL, EXTRACT_QUOTES); |
| if (r == 0) |
| break; |
| if (r == -ENOMEM) |
| return log_oom(); |
| if (r < 0) |
| return log_warning_errno(r, "Failed to add parse SYSTEMD_ALIAS for %s: %m", sysfs); |
| |
| if (!path_is_absolute(word)) |
| log_warning("SYSTEMD_ALIAS for %s is not an absolute path, ignoring: %s", sysfs, word); |
| else if (!path_is_normalized(word)) |
| log_warning("SYSTEMD_ALIAS for %s is not a normalized path, ignoring: %s", sysfs, word); |
| else |
| (void) device_setup_unit(m, dev, word, false); |
| } |
| |
| return 0; |
| } |
| |
| static void device_found_changed(Device *d, DeviceFound previous, DeviceFound now) { |
| assert(d); |
| |
| /* Didn't exist before, but does now? if so, generate a new invocation ID for it */ |
| if (previous == DEVICE_NOT_FOUND && now != DEVICE_NOT_FOUND) |
| (void) unit_acquire_invocation_id(UNIT(d)); |
| |
| if (FLAGS_SET(now, DEVICE_FOUND_UDEV)) |
| /* When the device is known to udev we consider it plugged. */ |
| device_set_state(d, DEVICE_PLUGGED); |
| else if (now != DEVICE_NOT_FOUND && !FLAGS_SET(previous, DEVICE_FOUND_UDEV)) |
| /* If the device has not been seen by udev yet, but is now referenced by the kernel, then we assume the |
| * kernel knows it now, and udev might soon too. */ |
| device_set_state(d, DEVICE_TENTATIVE); |
| else |
| /* If nobody sees the device, or if the device was previously seen by udev and now is only referenced |
| * from the kernel, then we consider the device is gone, the kernel just hasn't noticed it yet. */ |
| device_set_state(d, DEVICE_DEAD); |
| } |
| |
| static void device_update_found_one(Device *d, DeviceFound found, DeviceFound mask) { |
| assert(d); |
| |
| if (MANAGER_IS_RUNNING(UNIT(d)->manager)) { |
| DeviceFound n, previous; |
| |
| /* When we are already running, then apply the new mask right-away, and trigger state changes |
| * right-away */ |
| |
| n = (d->found & ~mask) | (found & mask); |
| if (n == d->found) |
| return; |
| |
| previous = d->found; |
| d->found = n; |
| |
| device_found_changed(d, previous, n); |
| } else |
| /* We aren't running yet, let's apply the new mask to the shadow variable instead, which we'll apply as |
| * soon as we catch-up with the state. */ |
| d->enumerated_found = (d->enumerated_found & ~mask) | (found & mask); |
| } |
| |
| static void device_update_found_by_sysfs(Manager *m, const char *sysfs, DeviceFound found, DeviceFound mask) { |
| Device *d, *l, *n; |
| |
| assert(m); |
| assert(sysfs); |
| |
| if (mask == 0) |
| return; |
| |
| l = hashmap_get(m->devices_by_sysfs, sysfs); |
| LIST_FOREACH_SAFE(same_sysfs, d, n, l) |
| device_update_found_one(d, found, mask); |
| } |
| |
| static int device_update_found_by_name(Manager *m, const char *path, DeviceFound found, DeviceFound mask) { |
| _cleanup_free_ char *e = NULL; |
| Unit *u; |
| int r; |
| |
| assert(m); |
| assert(path); |
| |
| if (mask == 0) |
| return 0; |
| |
| r = unit_name_from_path(path, ".device", &e); |
| if (r < 0) |
| return log_error_errno(r, "Failed to generate unit name from device path: %m"); |
| |
| u = manager_get_unit(m, e); |
| if (!u) |
| return 0; |
| |
| device_update_found_one(DEVICE(u), found, mask); |
| return 0; |
| } |
| |
| static bool device_is_ready(struct udev_device *dev) { |
| const char *ready; |
| |
| assert(dev); |
| |
| ready = udev_device_get_property_value(dev, "SYSTEMD_READY"); |
| if (!ready) |
| return true; |
| |
| return parse_boolean(ready) != 0; |
| } |
| |
| static Unit *device_following(Unit *u) { |
| Device *d = DEVICE(u); |
| Device *other, *first = NULL; |
| |
| assert(d); |
| |
| if (startswith(u->id, "sys-")) |
| return NULL; |
| |
| /* Make everybody follow the unit that's named after the sysfs path */ |
| for (other = d->same_sysfs_next; other; other = other->same_sysfs_next) |
| if (startswith(UNIT(other)->id, "sys-")) |
| return UNIT(other); |
| |
| for (other = d->same_sysfs_prev; other; other = other->same_sysfs_prev) { |
| if (startswith(UNIT(other)->id, "sys-")) |
| return UNIT(other); |
| |
| first = other; |
| } |
| |
| return UNIT(first); |
| } |
| |
| static int device_following_set(Unit *u, Set **_set) { |
| Device *d = DEVICE(u), *other; |
| _cleanup_set_free_ Set *set = NULL; |
| int r; |
| |
| assert(d); |
| assert(_set); |
| |
| if (LIST_JUST_US(same_sysfs, d)) { |
| *_set = NULL; |
| return 0; |
| } |
| |
| set = set_new(NULL); |
| if (!set) |
| return -ENOMEM; |
| |
| LIST_FOREACH_AFTER(same_sysfs, other, d) { |
| r = set_put(set, other); |
| if (r < 0) |
| return r; |
| } |
| |
| LIST_FOREACH_BEFORE(same_sysfs, other, d) { |
| r = set_put(set, other); |
| if (r < 0) |
| return r; |
| } |
| |
| *_set = TAKE_PTR(set); |
| return 1; |
| } |
| |
| static void device_shutdown(Manager *m) { |
| assert(m); |
| |
| m->udev_event_source = sd_event_source_unref(m->udev_event_source); |
| m->udev_monitor = udev_monitor_unref(m->udev_monitor); |
| m->devices_by_sysfs = hashmap_free(m->devices_by_sysfs); |
| } |
| |
| static void device_enumerate(Manager *m) { |
| _cleanup_(udev_enumerate_unrefp) struct udev_enumerate *e = NULL; |
| struct udev_list_entry *item = NULL, *first = NULL; |
| int r; |
| |
| assert(m); |
| |
| if (!m->udev_monitor) { |
| m->udev_monitor = udev_monitor_new_from_netlink(m->udev, "udev"); |
| if (!m->udev_monitor) { |
| log_error_errno(errno, "Failed to allocate udev monitor: %m"); |
| goto fail; |
| } |
| |
| /* This will fail if we are unprivileged, but that |
| * should not matter much, as user instances won't run |
| * during boot. */ |
| (void) udev_monitor_set_receive_buffer_size(m->udev_monitor, 128*1024*1024); |
| |
| r = udev_monitor_filter_add_match_tag(m->udev_monitor, "systemd"); |
| if (r < 0) { |
| log_error_errno(r, "Failed to add udev tag match: %m"); |
| goto fail; |
| } |
| |
| r = udev_monitor_enable_receiving(m->udev_monitor); |
| if (r < 0) { |
| log_error_errno(r, "Failed to enable udev event reception: %m"); |
| goto fail; |
| } |
| |
| r = sd_event_add_io(m->event, &m->udev_event_source, udev_monitor_get_fd(m->udev_monitor), EPOLLIN, device_dispatch_io, m); |
| if (r < 0) { |
| log_error_errno(r, "Failed to watch udev file descriptor: %m"); |
| goto fail; |
| } |
| |
| (void) sd_event_source_set_description(m->udev_event_source, "device"); |
| } |
| |
| e = udev_enumerate_new(m->udev); |
| if (!e) { |
| log_error_errno(errno, "Failed to alloacte udev enumerator: %m"); |
| goto fail; |
| } |
| |
| r = udev_enumerate_add_match_tag(e, "systemd"); |
| if (r < 0) { |
| log_error_errno(r, "Failed to create udev tag enumeration: %m"); |
| goto fail; |
| } |
| |
| r = udev_enumerate_add_match_is_initialized(e); |
| if (r < 0) { |
| log_error_errno(r, "Failed to install initialization match into enumeration: %m"); |
| goto fail; |
| } |
| |
| r = udev_enumerate_scan_devices(e); |
| if (r < 0) { |
| log_error_errno(r, "Failed to enumerate devices: %m"); |
| goto fail; |
| } |
| |
| first = udev_enumerate_get_list_entry(e); |
| udev_list_entry_foreach(item, first) { |
| _cleanup_(udev_device_unrefp) struct udev_device *dev = NULL; |
| const char *sysfs; |
| |
| sysfs = udev_list_entry_get_name(item); |
| |
| dev = udev_device_new_from_syspath(m->udev, sysfs); |
| if (!dev) { |
| if (errno == ENOMEM) { |
| log_oom(); |
| goto fail; |
| } |
| |
| /* If we can't create a device, don't bother, it probably just disappeared. */ |
| log_debug_errno(errno, "Failed to create udev device object for %s: %m", sysfs); |
| continue; |
| } |
| |
| if (!device_is_ready(dev)) |
| continue; |
| |
| (void) device_process_new(m, dev); |
| device_update_found_by_sysfs(m, sysfs, DEVICE_FOUND_UDEV, DEVICE_FOUND_UDEV); |
| } |
| |
| return; |
| |
| fail: |
| device_shutdown(m); |
| } |
| |
| static void device_propagate_reload_by_sysfs(Manager *m, const char *sysfs) { |
| Device *d, *l, *n; |
| int r; |
| |
| assert(m); |
| assert(sysfs); |
| |
| l = hashmap_get(m->devices_by_sysfs, sysfs); |
| LIST_FOREACH_SAFE(same_sysfs, d, n, l) { |
| if (d->state == DEVICE_DEAD) |
| continue; |
| |
| r = manager_propagate_reload(m, UNIT(d), JOB_REPLACE, NULL); |
| if (r < 0) |
| log_warning_errno(r, "Failed to propagate reload, ignoring: %m"); |
| } |
| } |
| |
| static int device_dispatch_io(sd_event_source *source, int fd, uint32_t revents, void *userdata) { |
| _cleanup_(udev_device_unrefp) struct udev_device *dev = NULL; |
| Manager *m = userdata; |
| const char *action, *sysfs; |
| int r; |
| |
| assert(m); |
| |
| if (revents != EPOLLIN) { |
| static RATELIMIT_DEFINE(limit, 10*USEC_PER_SEC, 5); |
| |
| if (ratelimit_below(&limit)) |
| log_warning("Failed to get udev event"); |
| if (!(revents & EPOLLIN)) |
| return 0; |
| } |
| |
| /* |
| * libudev might filter-out devices which pass the bloom |
| * filter, so getting NULL here is not necessarily an error. |
| */ |
| dev = udev_monitor_receive_device(m->udev_monitor); |
| if (!dev) |
| return 0; |
| |
| sysfs = udev_device_get_syspath(dev); |
| if (!sysfs) { |
| log_error("Failed to get udev sys path."); |
| return 0; |
| } |
| |
| action = udev_device_get_action(dev); |
| if (!action) { |
| log_error("Failed to get udev action string."); |
| return 0; |
| } |
| |
| if (streq(action, "change")) |
| device_propagate_reload_by_sysfs(m, sysfs); |
| |
| /* A change event can signal that a device is becoming ready, in particular if |
| * the device is using the SYSTEMD_READY logic in udev |
| * so we need to reach the else block of the follwing if, even for change events */ |
| if (streq(action, "remove")) { |
| r = swap_process_device_remove(m, dev); |
| if (r < 0) |
| log_warning_errno(r, "Failed to process swap device remove event, ignoring: %m"); |
| |
| /* If we get notified that a device was removed by |
| * udev, then it's completely gone, hence unset all |
| * found bits */ |
| device_update_found_by_sysfs(m, sysfs, 0, DEVICE_FOUND_UDEV|DEVICE_FOUND_MOUNT|DEVICE_FOUND_SWAP); |
| |
| } else if (device_is_ready(dev)) { |
| |
| (void) device_process_new(m, dev); |
| |
| r = swap_process_device_new(m, dev); |
| if (r < 0) |
| log_warning_errno(r, "Failed to process swap device new event, ignoring: %m"); |
| |
| manager_dispatch_load_queue(m); |
| |
| /* The device is found now, set the udev found bit */ |
| device_update_found_by_sysfs(m, sysfs, DEVICE_FOUND_UDEV, DEVICE_FOUND_UDEV); |
| |
| } else { |
| /* The device is nominally around, but not ready for |
| * us. Hence unset the udev bit, but leave the rest |
| * around. */ |
| |
| device_update_found_by_sysfs(m, sysfs, 0, DEVICE_FOUND_UDEV); |
| } |
| |
| return 0; |
| } |
| |
| static bool device_supported(void) { |
| static int read_only = -1; |
| |
| /* If /sys is read-only we don't support device units, and any |
| * attempts to start one should fail immediately. */ |
| |
| if (read_only < 0) |
| read_only = path_is_read_only_fs("/sys"); |
| |
| return read_only <= 0; |
| } |
| |
| static int validate_node(Manager *m, const char *node, struct udev_device **ret) { |
| struct stat st; |
| int r; |
| |
| assert(m); |
| assert(node); |
| assert(ret); |
| |
| /* Validates a device node that showed up in /proc/swaps or /proc/self/mountinfo if it makes sense for us to |
| * track. Note that this validator is fine within missing device nodes, but not with badly set up ones! */ |
| |
| if (!path_startswith(node, "/dev")) { |
| *ret = NULL; |
| return 0; /* bad! */ |
| } |
| |
| if (stat(node, &st) < 0) { |
| if (errno != ENOENT) |
| return log_error_errno(errno, "Failed to stat() device node file %s: %m", node); |
| |
| *ret = NULL; |
| return 1; /* good! (though missing) */ |
| |
| } else { |
| _cleanup_(udev_device_unrefp) struct udev_device *dev = NULL; |
| |
| r = udev_device_new_from_stat_rdev(m->udev, &st, &dev); |
| if (r == -ENOENT) { |
| *ret = NULL; |
| return 1; /* good! (though missing) */ |
| } else if (r == -ENOTTY) { |
| *ret = NULL; |
| return 0; /* bad! (not a device node but some other kind of file system node) */ |
| } else if (r < 0) |
| return log_error_errno(r, "Failed to get udev device from devnum %u:%u: %m", major(st.st_rdev), minor(st.st_rdev)); |
| |
| *ret = TAKE_PTR(dev); |
| return 1; /* good! */ |
| } |
| } |
| |
| void device_found_node(Manager *m, const char *node, DeviceFound found, DeviceFound mask) { |
| int r; |
| |
| assert(m); |
| assert(node); |
| |
| if (!device_supported()) |
| return; |
| |
| if (mask == 0) |
| return; |
| |
| /* This is called whenever we find a device referenced in /proc/swaps or /proc/self/mounts. Such a device might |
| * be mounted/enabled at a time where udev has not finished probing it yet, and we thus haven't learned about |
| * it yet. In this case we will set the device unit to "tentative" state. |
| * |
| * This takes a pair of DeviceFound flags parameters. The 'mask' parameter is a bit mask that indicates which |
| * bits of 'found' to copy into the per-device DeviceFound flags field. Thus, this function may be used to set |
| * and unset individual bits in a single call, while merging partially with previous state. */ |
| |
| if ((found & mask) != 0) { |
| _cleanup_(udev_device_unrefp) struct udev_device *dev = NULL; |
| |
| /* If the device is known in the kernel and newly appeared, then we'll create a device unit for it, |
| * under the name referenced in /proc/swaps or /proc/self/mountinfo. But first, let's validate if |
| * everything is alright with the device node. */ |
| |
| r = validate_node(m, node, &dev); |
| if (r <= 0) |
| return; /* Don't create a device unit for this if the device node is borked. */ |
| |
| (void) device_setup_unit(m, dev, node, false); |
| } |
| |
| /* Update the device unit's state, should it exist */ |
| (void) device_update_found_by_name(m, node, found, mask); |
| } |
| |
| bool device_shall_be_bound_by(Unit *device, Unit *u) { |
| assert(device); |
| assert(u); |
| |
| if (u->type != UNIT_MOUNT) |
| return false; |
| |
| return DEVICE(device)->bind_mounts; |
| } |
| |
| const UnitVTable device_vtable = { |
| .object_size = sizeof(Device), |
| .sections = |
| "Unit\0" |
| "Device\0" |
| "Install\0", |
| |
| .gc_jobs = true, |
| |
| .init = device_init, |
| .done = device_done, |
| .load = unit_load_fragment_and_dropin_optional, |
| |
| .coldplug = device_coldplug, |
| .catchup = device_catchup, |
| |
| .serialize = device_serialize, |
| .deserialize_item = device_deserialize_item, |
| |
| .dump = device_dump, |
| |
| .active_state = device_active_state, |
| .sub_state_to_string = device_sub_state_to_string, |
| |
| .bus_vtable = bus_device_vtable, |
| |
| .following = device_following, |
| .following_set = device_following_set, |
| |
| .enumerate = device_enumerate, |
| .shutdown = device_shutdown, |
| .supported = device_supported, |
| |
| .status_message_formats = { |
| .starting_stopping = { |
| [0] = "Expecting device %s...", |
| }, |
| .finished_start_job = { |
| [JOB_DONE] = "Found device %s.", |
| [JOB_TIMEOUT] = "Timed out waiting for device %s.", |
| }, |
| }, |
| }; |