NEWS: mention 99-default.link and NamePolicy

[elogind.git] / man / systemd.resource-control.xml

diff --git a/man/systemd.resource-control.xml b/man/systemd.resource-control.xml
index fcfe861256ce3ad584285fdf255b905c43dab564..e923b6da867cf1363a13a725bb8e25174792b157 100644 (file)
--- a/man/systemd.resource-control.xml
+++ b/man/systemd.resource-control.xml
@@ -226,14 +226,15 @@ along with systemd; If not, see <http://www.gnu.org/licenses/>.
           case the backing block device of the file system of the file
           is used. If the bandwidth is suffixed with K, M, G, or T,
           the specified bandwidth is parsed as Kilobytes, Megabytes,
-          Gigabytes, or Terabytes, respectively (Example:
+          Gigabytes, or Terabytes, respectively, to the base of
+          1000. (Example:
           "/dev/disk/by-path/pci-0000:00:1f.2-scsi-0:0:0:0 5M"). This
           controls the <literal>blkio.read_bps_device</literal> and
           <literal>blkio.write_bps_device</literal> control group
           attributes. Use this option multiple times to set bandwidth
           limits for multiple devices. For details about these control
-          group attributes, see
-          <ulink url="https://www.kernel.org/doc/Documentation/cgroups/blkio-controller.txt">blkio-controller.txt</ulink>.
+          group attributes, see <ulink
+          url="https://www.kernel.org/doc/Documentation/cgroups/blkio-controller.txt">blkio-controller.txt</ulink>.
           </para>
 
           <para>Implies
@@ -247,17 +248,31 @@ along with systemd; If not, see <http://www.gnu.org/licenses/>.
         <listitem>
           <para>Control access to specific device nodes by the
           executed processes. Takes two space-separated strings: a
-          device node path (such as <filename>/dev/null</filename>)
-          followed by a combination of <constant>r</constant>,
-          <constant>w</constant>, <constant>m</constant> to control
+          device node specifier followed by a combination of
+          <constant>r</constant>, <constant>w</constant>,
+          <constant>m</constant> to control
           <emphasis>r</emphasis>eading, <emphasis>w</emphasis>riting,
-          or creation of the specific device node by the unit
+          or creation of the specific device node(s) by the unit
           (<emphasis>m</emphasis>knod), respectively. This controls
           the <literal>devices.allow</literal> and
           <literal>devices.deny</literal> control group
-          attributes. For details about these control group attributes,
-          see <ulink
+          attributes. For details about these control group
+          attributes, see <ulink
           url="https://www.kernel.org/doc/Documentation/cgroups/devices.txt">devices.txt</ulink>.</para>
+
+          <para>The device node specifier is either a path to a device
+          node in the file system, starting with
+          <filename>/dev/</filename>, or a string starting with either
+          <literal>char-</literal> or <literal>block-</literal>
+          followed by a device group name, as listed in
+          <filename>/proc/devices</filename>. The latter is useful to
+          whitelist all current and future devices belonging to a
+          specific device group at once. Examples:
+          <filename>/dev/sda5</filename> is a path to a device node,
+          referring to an ATA or SCSI block
+          device. <literal>char-pts</literal> and
+          <literal>char-alsa</literal> are specifiers for all pseudo
+          TTYs and all ALSA sound devices, respectively.</para>
         </listitem>
       </varlistentry>