diff options
| -rw-r--r-- | man/systemctl.xml | 27 | ||||
| -rw-r--r-- | src/systemctl/systemctl.c | 63 |
2 files changed, 89 insertions, 1 deletions
diff --git a/man/systemctl.xml b/man/systemctl.xml index 9e113eb0fe..29481e7182 100644 --- a/man/systemctl.xml +++ b/man/systemctl.xml @@ -1159,6 +1159,33 @@ <listitem><para>Hibernate the system.</para></listitem> </varlistentry> + <varlistentry> + <term><command>switch-root [ROOT] [INIT]</command></term> + + <listitem><para>Switches to a + different root directory and executes + a new system manager process below + it. This is intended for usage in + initial RAM disks ("initrd"), and will + transition from the initrd's system + manager process (a.k.a "init" process) + to the main system manager + process. Takes two arguments: the + directory to make the new root + directory, and the path to the new + system manager binary below it to + execute as PID 1. If the latter is + ommitted or the empty string, a + systemd binary will automatically be + searched for and used as init. If the + system manager path is ommitted or + equal the empty string the state of + the initrd's system manager process is + passed to the main system manager, + which allows later introspection of the + state of the services involved in the + initrd boot.</para></listitem> + </varlistentry> </variablelist> </refsect1> diff --git a/src/systemctl/systemctl.c b/src/systemctl/systemctl.c index 4708a35835..0034c55384 100644 --- a/src/systemctl/systemctl.c +++ b/src/systemctl/systemctl.c @@ -3580,6 +3580,65 @@ finish: return r; } +static int switch_root(DBusConnection *bus, char **args) { + DBusMessage *m = NULL, *reply = NULL; + unsigned l; + const char *root, *init; + DBusError error; + int r; + + dbus_error_init(&error); + + l = strv_length(args); + if (l < 2 || l > 3) { + log_error("Wrong number of arguments."); + return -EINVAL; + } + + root = args[1]; + init = l >= 3 ? args[2] : ""; + + m = dbus_message_new_method_call( + "org.freedesktop.systemd1", + "/org/freedesktop/systemd1", + "org.freedesktop.systemd1.Manager", + "SwitchRoot"); + if (!m) { + log_error("Could not allocate message."); + return -ENOMEM; + } + + if (!dbus_message_append_args( + m, + DBUS_TYPE_STRING, &root, + DBUS_TYPE_STRING, &init, + DBUS_TYPE_INVALID)) { + log_error("Could not append arguments to message."); + r = -ENOMEM; + goto finish; + } + + reply = dbus_connection_send_with_reply_and_block(bus, m, -1, &error); + if (!reply) { + log_error("Failed to issue method call: %s", bus_error_message(&error)); + r = -EIO; + goto finish; + } + + r = 0; + +finish: + if (m) + dbus_message_unref(m); + + if (reply) + dbus_message_unref(reply); + + dbus_error_free(&error); + + return r; +} + static int set_environment(DBusConnection *bus, char **args) { DBusMessage *m = NULL, *reply = NULL; DBusError error; @@ -4220,6 +4279,7 @@ static int systemctl_help(void) { " reboot Shut down and reboot the system\n" " kexec Shut down and reboot the system with kexec\n" " exit Request user instance exit\n" + " switch-root [ROOT] [INIT] Change to a different root file system\n" " suspend Suspend the system\n" " hibernate Hibernate the system\n", program_invocation_short_name); @@ -5169,7 +5229,8 @@ static int systemctl_main(DBusConnection *bus, int argc, char *argv[], DBusError { "preset", MORE, 2, enable_unit }, { "mask", MORE, 2, enable_unit }, { "unmask", MORE, 2, enable_unit }, - { "link", MORE, 2, enable_unit } + { "link", MORE, 2, enable_unit }, + { "switch-root", MORE, 2, switch_root }, }; int left; |