kernel-install: Add uki layout

Currently the kernel-install man page only documents the bls layout for use
with the boot loader spec type #1. 90-loaderentry.install uses this layout to
generate loader entries and copy the kernel image and initrd to $BOOT.

This commit documents a second layout "uki" and adds 90-uki-copy.install,
which copies a UKI "uki.efi" from the staging area or any file with the .efi
extension given on the command line to
$BOOT/EFI/Linux/$ENTRY_TOKEN-$KERNEl_VERSION(+$TRIES).efi

This allows for both locally generated and distro-provided UKIs to be handled
by kernel-install.

1 files changed, 32 insertions, 6 deletions

diff --git a/man/kernel-install.xml b/man/kernel-install.xml
index 29b0d8eb54..f3fdc961f4 100644
--- a/man/kernel-install.xml
+++ b/man/kernel-install.xml
@@ -108,6 +108,14 @@
             is missing), or "Linux <replaceable>KERNEL-VERSION</replaceable>", if unset.</para>
 
             <para>If <varname>$KERNEL_INSTALL_LAYOUT</varname> is not "bls", this plugin does nothing.</para></listitem>
+
+            <listitem><para><filename>90-uki-copy.install</filename> copies a file
+            <filename>uki.efi</filename> from <varname>$KERNEL_INSTALL_STAGING_AREA</varname> or if it does
+            not exist the <replaceable>KERNEL-IMAGE</replaceable> argument, iff it has a
+            <literal>.efi</literal> extension, to
+            <filename>$BOOT/EFI/Linux/<replaceable>ENTRY-TOKEN</replaceable>-<replaceable>KERNEL-VERSION</replaceable>.efi</filename>.</para>
+
+            <para>If <varname>$KERNEL_INSTALL_LAYOUT</varname> is not "uki", this plugin does nothing.</para></listitem>
           </itemizedlist>
         </listitem>
       </varlistentry>
@@ -132,6 +140,9 @@
 
             <listitem><para><filename>90-loaderentry.install</filename> removes the file
             <filename>$BOOT/loader/entries/<replaceable>ENTRY-TOKEN</replaceable>-<replaceable>KERNEL-VERSION</replaceable>.conf</filename>.</para></listitem>
+
+            <listitem><para><filename>90-uki-copy.install</filename> removes the file
+            <filename>$BOOT/EFI/Linux/<replaceable>ENTRY-TOKEN</replaceable>-<replaceable>KERNEL-VERSION</replaceable>.efi</filename>.</para></listitem>
           </itemizedlist>
         </listitem>
       </varlistentry>
@@ -213,7 +224,7 @@
       (EFI System Partition) are mounted, and also conceptually referred to as <varname>$BOOT</varname>. Can
       be overridden by setting <varname>$BOOT_ROOT</varname> (see below).</para>
 
-      <para><varname>$KERNEL_INSTALL_LAYOUT=bls|other|...</varname> is set for the plugins to specify the
+      <para><varname>$KERNEL_INSTALL_LAYOUT=bls|uki|other|...</varname> is set for the plugins to specify the
       installation layout. Defaults to <option>bls</option> if
       <filename>$BOOT/<replaceable>ENTRY-TOKEN</replaceable></filename> exists, or <option>other</option>
       otherwise. Additional layout names may be defined by convention. If a plugin uses a special layout,
@@ -236,6 +247,18 @@
           </listitem>
         </varlistentry>
         <varlistentry>
+          <term>uki</term>
+          <listitem>
+            <para>Standard <ulink
+            url="https://uapi-group.org/specifications/specs/boot_loader_specification">Boot Loader
+            Specification</ulink> Type #2 layout, compatible with
+            <citerefentry><refentrytitle>systemd-boot</refentrytitle><manvolnum>7</manvolnum></citerefentry>:
+            unified kernel images under <filename>$BOOT/EFI/Linux</filename> as
+            <filename>$BOOT/EFI/Linux/<replaceable>ENTRY-TOKEN</replaceable>-<replaceable>KERNEL-VERSION</replaceable>[+<replaceable>TRIES</replaceable>].efi</filename>.</para>
+            <para>Implemented by <filename>90-uki-copy.install</filename>.</para>
+          </listitem>
+        </varlistentry>
+        <varlistentry>
           <term>other</term>
           <listitem>
             <para>Some other layout not understood natively by <command>kernel-install</command>.</para>
@@ -312,12 +335,15 @@
           <filename>/etc/kernel/tries</filename>
         </term>
           <listitem>
-            <para>Read by <filename>90-loaderentry.install</filename>. If this file exists a numeric value is read from
-            it and the naming of the generated entry file is slightly altered to include it as
-            <filename>$BOOT/loader/entries/<replaceable>MACHINE-ID</replaceable>-<replaceable>KERNEL-VERSION</replaceable>+<replaceable>TRIES</replaceable>.conf</filename>. This
+            <para>Read by <filename>90-loaderentry.install</filename> and
+            <filename>90-uki-copy.install</filename>. If this file exists a numeric value is read from it
+            and the naming of the generated entry file or UKI is slightly altered to include it as
+            <filename>$BOOT/loader/entries/<replaceable>ENTRY-TOKEN</replaceable>-<replaceable>KERNEL-VERSION</replaceable>+<replaceable>TRIES</replaceable>.conf</filename>
+            or
+            <filename>$BOOT/EFI/Linux/<replaceable>ENTRY-TOKEN</replaceable>-<replaceable>KERNEL-VERSION</replaceable>+<replaceable>TRIES</replaceable>.conf</filename>, respectively. This
             is useful for boot loaders such as
-            <citerefentry><refentrytitle>systemd-boot</refentrytitle><manvolnum>7</manvolnum></citerefentry> which
-            implement boot attempt counting with a counter embedded in the entry file name.
+            <citerefentry><refentrytitle>systemd-boot</refentrytitle><manvolnum>7</manvolnum></citerefentry>
+            which implement boot attempt counting with a counter embedded in the entry file name.
             <varname>$KERNEL_INSTALL_CONF_ROOT</varname> may be used to override the path.</para>
           </listitem>
       </varlistentry>