From a97dea93d28ba272613029e46a8a0b1f699729d8 Mon Sep 17 00:00:00 2001
From: Richard Maw <richard.maw@codethink.co.uk>
Date: Tue, 27 May 2014 14:58:14 +0000
Subject: Add initial version of initramfs script

---
 init                    | 107 ++++++++++++++++++++++++++++++++++++++++++++++++
 initramfs-scripts.morph |   5 +++
 2 files changed, 112 insertions(+)
 create mode 100644 init
 create mode 100644 initramfs-scripts.morph

diff --git a/init b/init
new file mode 100644
index 00000000..fa31c0e7
--- /dev/null
+++ b/init
@@ -0,0 +1,107 @@
+#!/bin/sh
+set -e
+
+# We need proc for reading the kernel command line
+mount -n -t proc none /proc
+
+set -- $(cat /proc/cmdline)
+
+# We don't want to leave mount points around
+umount /proc
+
+for arg; do
+    case "$arg" in
+    root=LABEL=*)
+        if [ x"$root_type" != x ]; then
+            echo "Warning, multiple root= specified, using latest."
+        fi
+        root_type=label
+        root="${arg#root=LABEL=}"
+        ;;
+    root=UUID=*)
+        if [ x"$root_type" != x ]; then
+            echo "Warning, multiple root= specified, using latest."
+        fi
+        root_type=uuid
+        root="${arg#root=UUID=}"
+        ;;
+    root=*)
+        if [ x"$root_type" != x ]; then
+            echo "Warning, multiple root= specified, using latest."
+        fi
+        root_type=disk
+        root="${arg#root=}"
+        ;;
+    rootflags=*)
+        if [ x"$rootflags" != x ]; then
+            echo "Warning, multiple rootflags= specified, using latest."
+        fi
+        rootflags=",${arg#rootflags=}"
+        ;;
+    rootfstype=*)
+        if [ x"$rootflags" != x ]; then
+            echo "Warning, multiple rootfstype= specified, using latest."
+        fi
+        rootfstype="${arg#rootfstype=}"
+        ;;
+    rootdelay=*)
+        if [ x"$rootflags" != x ]; then
+            echo "Warning, multiple rootdelay= specified, using latest."
+        fi
+        rootfstype="${arg#rootdelay=}"
+        ;;
+    ro)
+        ro=ro
+        ;;
+    rw)
+        ro=rw
+        ;;
+    init=*)
+        init="${arg#init=}"
+        ;;
+    esac
+done
+
+if [ x"$rootdelay" != x ]; then
+    sleep "$rootdelay"
+fi
+
+if [ x"$rootfstype" = x ]; then
+    # Warn that busybox may not be able to auto-detect rootfs type
+    cat <<\EOF
+Warning, rootfs type not specified, auto-detection of type is slow and
+may fail. Please add rootfstype=$type to kernel command line.
+EOF
+fi
+
+mount -n -t devtmpfs devtmpfs /dev
+case "$root_type" in
+disk)
+    mount -n -t "${rootfstype}" -o "${ro-rw}""$rootflags" "$root" /mnt
+    ;;
+label)
+    disk="$(findfs LABEL="$root")"
+    if [ x"$disk" = x ]; then
+        echo disk with label $root not found
+        blkid
+        exit 1
+    fi
+    mount -n -t "${rootfstype}" -o "${ro-rw}""$rootflags" "$disk" /mnt
+    ;;
+uuid)
+    disk="$(findfs UUID="$root")"
+    if [ x"$disk" = x ]; then
+        echo disk with UUID $root not found
+        blkid
+        exit 1
+    fi
+    mount -n -t "${rootfstype}" -o "${ro-rw}""$rootflags" "$disk" /mnt
+    ;;
+'')
+    echo "Error, no root specified"
+    exit 1
+    ;;
+esac
+umount -n /dev
+
+exec switch_root -c /dev/console /mnt "${init-/sbin/init}"
diff --git a/initramfs-scripts.morph b/initramfs-scripts.morph
new file mode 100644
index 00000000..77bba209
--- /dev/null
+++ b/initramfs-scripts.morph
@@ -0,0 +1,5 @@
+name: initramfs-scripts
+kind: chunk
+build-system: manual
+install-commands:
+- install -m 755 init "$DESTDIR/init"
-- 
cgit v1.2.1


From a3ddeed683d765f5c7638c23ca3b95a9914a37b6 Mon Sep 17 00:00:00 2001
From: Richard Maw <richard.maw@codethink.co.uk>
Date: Thu, 26 Mar 2015 14:06:18 +0000
Subject: Drop into /bin/sh on failure

Change-Id: Iff3f7d911088842d430e7946f7a1d4cb6edbfa93
---
 init | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/init b/init
index fa31c0e7..80bee3cf 100644
--- a/init
+++ b/init
@@ -1,5 +1,5 @@
 #!/bin/sh
-set -e
+trap 'exec /bin/sh' INT EXIT
 
 # We need proc for reading the kernel command line
 mount -n -t proc none /proc
-- 
cgit v1.2.1


From 062c5d3aece2e308aa7fc03acab1b3b6dd4270b2 Mon Sep 17 00:00:00 2001
From: Richard Maw <richard.maw@codethink.co.uk>
Date: Thu, 26 Mar 2015 14:06:30 +0000
Subject: Support rootwait (enabled by default)

Change-Id: Ie1cb0c136cb9bc2873d86bbc244dcacdcf85b65d
---
 init | 68 +++++++++++++++++++++++++++++++++++++++++++-------------------------
 1 file changed, 43 insertions(+), 25 deletions(-)

diff --git a/init b/init
index 80bee3cf..65bf6e87 100644
--- a/init
+++ b/init
@@ -9,6 +9,7 @@ set -- $(cat /proc/cmdline)
 # We don't want to leave mount points around
 umount /proc
 
+rootwait=true # defaults to off in the kernel, I think it's more useful on
 for arg; do
     case "$arg" in
     root=LABEL=*)
@@ -50,6 +51,12 @@ for arg; do
         fi
         rootfstype="${arg#rootdelay=}"
         ;;
+    rootwait)
+        rootwait=true
+        ;;
+    norootwait)
+        rootwait=false
+        ;;
     ro)
         ro=ro
         ;;
@@ -75,33 +82,44 @@ EOF
 fi
 
 mount -n -t devtmpfs devtmpfs /dev
-case "$root_type" in
-disk)
-    mount -n -t "${rootfstype}" -o "${ro-rw}""$rootflags" "$root" /mnt
-    ;;
-label)
-    disk="$(findfs LABEL="$root")"
-    if [ x"$disk" = x ]; then
-        echo disk with label $root not found
-        blkid
-        exit 1
-    fi
-    mount -n -t "${rootfstype}" -o "${ro-rw}""$rootflags" "$disk" /mnt
-    ;;
-uuid)
-    disk="$(findfs UUID="$root")"
-    if [ x"$disk" = x ]; then
-        echo disk with UUID $root not found
-        blkid
+while true; do
+    case "$root_type" in
+    disk)
+        if mount -n -t "${rootfstype}" -o "${ro-rw}""$rootflags" "$root" /mnt; then
+            break
+        else
+            echo disk $root not found
+            blkid
+        fi
+        ;;
+    label)
+        disk="$(findfs LABEL="$root")"
+        if [ x"$disk" = x ]; then
+            echo disk with label $root not found
+            blkid
+        else
+            mount -n -t "${rootfstype}" -o "${ro-rw}""$rootflags" "$disk" /mnt && break
+        fi
+        ;;
+    uuid)
+        disk="$(findfs UUID="$root")"
+        if [ x"$disk" = x ]; then
+            echo disk with UUID $root not found
+            blkid
+        else
+            mount -n -t "${rootfstype}" -o "${ro-rw}""$rootflags" "$disk" /mnt && break
+        fi
+        ;;
+    '')
+        echo "Error, no root specified"
         exit 1
+        ;;
+    esac
+    if "$rootwait"; then
+        echo Trying again in 0.5 seconds
+        sleep 0.5
     fi
-    mount -n -t "${rootfstype}" -o "${ro-rw}""$rootflags" "$disk" /mnt
-    ;;
-'')
-    echo "Error, no root specified"
-    exit 1
-    ;;
-esac
+done
 umount -n /dev
 
 exec switch_root -c /dev/console /mnt "${init-/sbin/init}"
-- 
cgit v1.2.1


From a16968232cbcffdf901650ac260689a1f3664dfe Mon Sep 17 00:00:00 2001
From: Richard Maw <richard.maw@codethink.co.uk>
Date: Tue, 19 May 2015 09:50:34 +0000
Subject: Convert build-system to autotools-like

This removes the need for an embedded morphology in the repository.

Change-Id: I0ceff8f9b12458f7a4d0d5af10a6eba32fb44041
---
 Makefile                | 9 +++++++++
 configure               | 1 +
 initramfs-scripts.morph | 5 -----
 3 files changed, 10 insertions(+), 5 deletions(-)
 create mode 100644 Makefile
 create mode 100755 configure
 delete mode 100644 initramfs-scripts.morph

diff --git a/Makefile b/Makefile
new file mode 100644
index 00000000..e00cf308
--- /dev/null
+++ b/Makefile
@@ -0,0 +1,9 @@
+
+SCRIPTS = init
+
+all:
+
+install: $(SCRIPTS)
+	for script in $^ ; do\
+	    install -D -m 755 "$$script" $(DESTDIR)/"$$script"; \
+	done
diff --git a/configure b/configure
new file mode 100755
index 00000000..1a248525
--- /dev/null
+++ b/configure
@@ -0,0 +1 @@
+#!/bin/sh
diff --git a/initramfs-scripts.morph b/initramfs-scripts.morph
deleted file mode 100644
index 77bba209..00000000
--- a/initramfs-scripts.morph
+++ /dev/null
@@ -1,5 +0,0 @@
-name: initramfs-scripts
-kind: chunk
-build-system: manual
-install-commands:
-- install -m 755 init "$DESTDIR/init"
-- 
cgit v1.2.1


From e5c71f0ca075bd29ffd55ec0c25804585bc21046 Mon Sep 17 00:00:00 2001
From: Richard Maw <richard.maw@codethink.co.uk>
Date: Tue, 19 May 2015 09:52:28 +0000
Subject: Add systemd shutdownramfs support

Systemd will, if there exists a /run/initramfs/shutdown executable,
pivot into /run/initramfs and exec /shutdown when shutting down.

This allows / to be unmounted, rather than just remounting read-only and
hoping for the best.

Change-Id: If42fc21380f74e039b02d9ef9b0491c24276f098
---
 Makefile |  2 +-
 shutdown | 66 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 67 insertions(+), 1 deletion(-)
 create mode 100644 shutdown

diff --git a/Makefile b/Makefile
index e00cf308..97ad4751 100644
--- a/Makefile
+++ b/Makefile
@@ -1,5 +1,5 @@
 
-SCRIPTS = init
+SCRIPTS = init shutdown
 
 all:
 
diff --git a/shutdown b/shutdown
new file mode 100644
index 00000000..09281dd3
--- /dev/null
+++ b/shutdown
@@ -0,0 +1,66 @@
+#!/bin/sh
+
+fail(){
+    echo "$@" >&2
+    # The behaviour on failure of systemd when shutting down without a
+    # shutdownramfs is to freeze if it fails, but the behaviour of an initramfs
+    # on failure is to drop you into a recovery shell. The latter seems more
+    # useful.
+    exec /bin/sh
+}
+
+startswith(){
+    # Filter out lines that don't start with $1
+    # grep ^EXPR is usually sufficient, but would require escaping of EXPR.
+    # Instead this compares the line to the line with its prefix stripped,
+    # so if the line is different, then it started with that prefix.
+    # It's ugly, but is less logic than escaping the regular expression and
+    # using grep, more reliable than not making any effort to escape, and
+    # less surprising than requiring the parameter to be pre-escaped.
+    while read -r line; do
+        if [ "${line#"$1"}" != "$line" ]; then
+            printf '%s\n' "$line"
+        fi
+    done
+}
+
+recursive_umount(){
+    # Recursively unmount every mountpoint under $1.
+    # This works by filtering to select mountpoints from mountinfo that start
+    # with the absolute path of the directory given.
+    # It unmounts in reverse-order, so that it may unmount dependent mounts
+    # first, and it has to handle the paths having octal escape sequences.
+    set -- "$(readlink -f "$1")"
+    cut -d' ' -f5 /proc/self/mountinfo | startswith "$1" \
+        | sort -r | while read -r mp; do
+        umount "$(echo -e "$mp")"
+    done
+}
+
+# Give the rootfs another chance to write its state to disk.
+sync
+
+# Kill any http://www.freedesktop.org/wiki/Software/systemd/RootStorageDaemons/
+# as we don't have any facility to cleanly shut them down in this initramfs.
+killall5
+
+# Recursively unmount the old root, so they have a chance of performing
+# unmount-time cleanup.
+recursive_umount /oldroot
+
+case "$1" in
+reboot|poweroff|halt)
+        if ! "$1" -f; then
+            fail "$1 command failed"
+        fi
+        ;;
+kexec)
+        # probably don't have this, but we'll try anyway
+        if ! kexec -e; then
+            fail "$1 command failed"
+        fi
+        ;;
+*)
+        fail "Unrecognized shutdown verb $1"
+        ;;
+esac
-- 
cgit v1.2.1