From eea4182c8d82424a0df7b2ceb4261a51f7cd6286 Mon Sep 17 00:00:00 2001
From: Zac Mrowicki <mrowicki@amazon.com>
Date: Fri, 22 Jan 2021 19:07:45 +0000
Subject: [PATCH] Add a systemd mount unit for CD-ROM devices

This change adds a mount unit that will mount a CD-ROM device located at
/dev/cdrom to /media/cdrom if that device exists.  systemd includes a
udev rule to symlink a suspected CD-ROM device to /dev/cdrom.  The
primary use of said device to supply user data to a bottlerocket host.
---
 packages/filesystem/filesystem.spec |  1 +
 packages/release/media-cdrom.mount  | 21 +++++++++++++++++++++
 packages/release/release.spec       |  6 +++++-
 3 files changed, 27 insertions(+), 1 deletion(-)
 create mode 100644 packages/release/media-cdrom.mount

diff --git a/packages/filesystem/filesystem.spec b/packages/filesystem/filesystem.spec
index 317f5484262..d74f22b66f8 100644
--- a/packages/filesystem/filesystem.spec
+++ b/packages/filesystem/filesystem.spec
@@ -29,6 +29,7 @@ mkdir -p %{buildroot}%{_cross_mandir}
 mkdir -p %{buildroot}%{_cross_localstatedir}
 mkdir -p %{buildroot}/{boot,dev,proc,root,run,sys,tmp}
 mkdir -p %{buildroot}/{home,local,media,mnt,opt,srv}
+mkdir -p %{buildroot}/media/cdrom
 
 ln -s .%{_cross_prefix} %{buildroot}%{_prefix}
 ln -s .%{_cross_bindir} %{buildroot}/bin
diff --git a/packages/release/media-cdrom.mount b/packages/release/media-cdrom.mount
new file mode 100644
index 00000000000..27777f785dd
--- /dev/null
+++ b/packages/release/media-cdrom.mount
@@ -0,0 +1,21 @@
+[Unit]
+Description=CD-ROM mount (/media/cdrom)
+# Only run this unit if /dev/cdrom exists and is tracked via systemd. (systemd
+# ships with a udev rule to tag and symlink the first suspected cdrom device to
+# /dev/cdrom)
+Requires=dev-cdrom.device
+After=dev-cdrom.device
+DefaultDependencies=no
+Conflicts=umount.target
+Before=local-fs.target umount.target
+
+[Mount]
+What=/dev/cdrom
+Where=/media/cdrom
+Type=iso9660
+Options=defaults,noexec
+
+[Install]
+# This dependency ensures that systemd attempts to run this unit if the device
+# exists.
+WantedBy=dev-cdrom.device
diff --git a/packages/release/release.spec b/packages/release/release.spec
index da99539b9e8..1bf20c01e8f 100644
--- a/packages/release/release.spec
+++ b/packages/release/release.spec
@@ -25,6 +25,9 @@ Source1008: opt.mount
 Source1009: var-lib-bottlerocket.mount
 Source1010: etc-cni.mount
 
+# CD-ROM mount
+Source1015: media-cdrom.mount
+
 # Mounts that require build-time edits.
 Source1020: var-lib-kernel-devel-lower.mount.in
 Source1021: usr-src-kernels.mount.in
@@ -104,7 +107,7 @@ EOF
 
 install -d %{buildroot}%{_cross_unitdir}
 install -p -m 0644 \
-  %{S:1002} %{S:1006} %{S:1007} %{S:1008} %{S:1009} %{S:1010} \
+  %{S:1002} %{S:1006} %{S:1007} %{S:1008} %{S:1009} %{S:1010} %{S:1015} \
   %{buildroot}%{_cross_unitdir}
 
 LOWERPATH=$(systemd-escape --path %{_cross_sharedstatedir}/kernel-devel/lower)
@@ -138,6 +141,7 @@ install -p -m 0644 %{S:201} %{buildroot}%{_cross_templatedir}/proxy-env
 %{_cross_unitdir}/var.mount
 %{_cross_unitdir}/opt.mount
 %{_cross_unitdir}/etc-cni.mount
+%{_cross_unitdir}/media-cdrom.mount
 %{_cross_unitdir}/*-lower.mount
 %{_cross_unitdir}/*-kernels.mount
 %{_cross_unitdir}/*-licenses.mount