diff --git a/man/udevadm.xml b/man/udevadm.xml
index a63a92cef2..ac3198b1f8 100644
--- a/man/udevadm.xml
+++ b/man/udevadm.xml
@@ -76,39 +76,40 @@
udevadm info
<arg choice="opt"><replaceable>options</replaceable></arg>
- <arg choice="opt"><replaceable>devpath</replaceable>|<replaceable>file</replaceable></arg>
+ <arg choice="opt"><replaceable>devpath</replaceable>|<replaceable>file</replaceable>|<replaceable>unit</replaceable></arg>
- Queries the udev database for device information
- stored in the udev database. It can also query the properties
- of a device from its sysfs representation to help creating udev
- rules that match this device.
+ Query the udev database for device information.
+
+ A positional argument should be used to specify a device. It may be a device name (in which case
+ it must start with /dev/), a sys path (in which case it must start with
+ /sys/), or a systemd device unit name (in which case it must end with
+ .device, see
+ systemd.device5).
+
+
- Query the database for the specified type of device
- data. It needs the or
- to identify the specified device.
+ Query the database for the specified type of device data.
Valid TYPEs are:
name, symlink,
path, property,
all.
+
- The /sys path of the device to
- query, e.g.
- /sys/class/block/sda.
- Note that this option usually is not very useful, since
- udev can guess the type of the
- argument, so udevadm info
- --path=/class/block/sda is equivalent to
- udevadm info /sys/class/block/sda.
+ The /sys path of the device to query, e.g.
+ /sys/class/block/sda. This option is an alternative to
+ the positional argument with a /sys/ prefix. udevadm info
+ --path=/class/block/sda is equivalent to udevadm info
+ /sys/class/block/sda.
@@ -116,11 +117,9 @@
The name of the device node or a symlink to query,
- e.g. /dev/sda.
- Note that this option usually is not very useful, since
- udev can guess the type of the
- argument, so udevadm info --name=sda is
- equivalent to udevadm info /dev/sda.
+ e.g. /dev/sda. This option is an alternative to the
+ positional argument with a /dev/ prefix. udevadm info
+ --name=sda is equivalent to udevadm info /dev/sda.
@@ -179,17 +178,17 @@
-
- In addition, an optional positional argument can be used
- to specify a device name or a sys path. It must start with
- /dev or /sys
- respectively.udevadm trigger
<arg choice="opt"><replaceable>options</replaceable></arg>
- <arg choice="opt" rep="repeat"><replaceable>devpath</replaceable>|<replaceable>file</replaceable></arg>
+ devpath|file|unit
+
Request device events from the kernel. Primarily used to replay events at system coldplug time.
+
+ Takes one or more device specifications as arguments. See the description of info
+ above.
+
diff --git a/src/udev/udevadm-info.c b/src/udev/udevadm-info.c
index ff4cf4ec45..31a6291279 100644
--- a/src/udev/udevadm-info.c
+++ b/src/udev/udevadm-info.c
@@ -440,7 +440,7 @@ int info_main(int argc, char *argv[], void *userdata) {
r = find_device(argv[optind], NULL, &device);
if (r == -EINVAL)
- return log_error_errno(r, "Bad argument \"%s\", an absolute path in /dev/ or /sys expected: %m",
+ return log_error_errno(r, "Bad argument \"%s\", expected an absolute path in /dev/ or /sys or a unit name: %m",
argv[optind]);
if (r < 0)
return log_error_errno(r, "Unknown device \"%s\": %m", argv[optind]);
diff --git a/src/udev/udevadm-util.c b/src/udev/udevadm-util.c
index ef0dc564ce..557982b23d 100644
--- a/src/udev/udevadm-util.c
+++ b/src/udev/udevadm-util.c
@@ -6,18 +6,31 @@
#include "device-private.h"
#include "path-util.h"
#include "udevadm-util.h"
+#include "unit-name.h"
int find_device(const char *id, const char *prefix, sd_device **ret) {
- _cleanup_free_ char *buf = NULL;
+ _cleanup_free_ char *path = NULL;
+ int r;
assert(id);
assert(ret);
- if (prefix && !path_startswith(id, prefix)) {
- buf = path_join(prefix, id);
- if (!buf)
- return -ENOMEM;
- id = buf;
+ if (prefix) {
+ if (!path_startswith(id, prefix)) {
+ id = path = path_join(prefix, id);
+ if (!path)
+ return -ENOMEM;
+ }
+ } else {
+ /* In cases where the argument is generic (no prefix specified),
+ * check if the argument looks like a device unit name. */
+ if (unit_name_is_valid(id, UNIT_NAME_PLAIN) &&
+ unit_name_to_type(id) == UNIT_DEVICE) {
+ r = unit_name_to_path(id, &path);
+ if (r < 0)
+ return log_debug_errno(r, "Failed to convert \"%s\" to a device path: %m", id);
+ id = path;
+ }
}
if (path_startswith(id, "/sys/"))