fs-init: add recipe to extend rootfs partition on eMMC

- on Colbri/Apalis T30 the rootfs is downloaded in a minimum size.
  On first boot this filesystem is resized to fill its full partion.
  This slows down IO responsivness during the first 5 minutes.

4 files changed, 88 insertions, 0 deletions

diff --git a/recipes-core/fs-init/files/COPYING b/recipes-core/fs-init/files/COPYING
new file mode 100644
index 0000000..040e990
--- /dev/null
+++ b/recipes-core/fs-init/files/COPYING
@@ -0,0 +1,5 @@
+This piece is software is provided by Toradex AG as sample code.
+There is no warranty for the program.
+Toradex AG put this program in public domain, uncopyrighted.
+
+Renens, Swizterland, 2008-10-23
diff --git a/recipes-core/fs-init/files/resizefs.service b/recipes-core/fs-init/files/resizefs.service
new file mode 100644
index 0000000..7dbbb99
--- /dev/null
+++ b/recipes-core/fs-init/files/resizefs.service
@@ -0,0 +1,9 @@
+[Unit]
+Description=start resize script to increase rootfs to its partitions full size
+
+[Service]
+Type=simple
+ExecStart=/bin/sh -c 'sleep 5 ; /usr/sbin/resizefs.sh'
+
+[Install]
+WantedBy=graphical.target
diff --git a/recipes-core/fs-init/files/resizefs.sh b/recipes-core/fs-init/files/resizefs.sh
new file mode 100755
index 0000000..24ea1fd
--- /dev/null
+++ b/recipes-core/fs-init/files/resizefs.sh
@@ -0,0 +1,49 @@
+#!/bin/sh
+# resize the rootfs ext filesystem size to its full partition size
+# usually used on first boot in a postinstall script
+# or set in an autostart file from a postinstall script
+
+DISK="mmcblk0"
+PART="mmcblk0p1"
+
+logger "resizing $PART to fill its full partition size"
+# get the disk total size
+DISK_SIZE=`cat /sys/block/$DISK/size`
+
+# get partition start and size
+PART_OFF=`cat /sys/block/$DISK/$PART/start`
+PART_SIZE=`cat /sys/block/$DISK/$PART/size`
+
+# calculate size after the partition to the end of disk
+SPARE=`expr $DISK_SIZE - $PART_OFF - $PART_SIZE`
+
+# new filesystem size, it must not overlap the secondary gpt header
+# assume 1024kB as GPT size (is 34 sectors)
+if [ $SPARE -lt 2048 ]
+then
+	FSSIZE=`expr $PART_SIZE - 2048`
+else
+	FSSIZE=$PART_SIZE
+fi
+
+# resize now
+
+#reduce I/O load by doing this in 32M increments
+#idea stolen from here:
+#https://codereview.chromium.org/551127
+
+NEXTSIZE=`expr 320 \* 1024 \* 2`
+while [ $NEXTSIZE -lt $FSSIZE ]; do
+	FSSIZEMEG=`expr $NEXTSIZE / 2 / 1024`"M"
+	resize2fs /dev/$PART $FSSIZEMEG
+	sleep 1
+	NEXTSIZE=`expr $NEXTSIZE + 32 \* 1024 \* 2`
+done
+FSSIZEMEG=`expr $FSSIZE / 2 / 1024`"M"
+resize2fs /dev/$PART $FSSIZEMEG
+
+#job done, remove it from systemd services
+systemctl disable resizefs.service
+
+logger "resizing $PART finished, new size is $FSSIZEMEG"
+
diff --git a/recipes-core/fs-init/fs-init.bb b/recipes-core/fs-init/fs-init.bb
new file mode 100644
index 0000000..b2b61a8
--- /dev/null
+++ b/recipes-core/fs-init/fs-init.bb
@@ -0,0 +1,25 @@
+DESCRIPTION = "Script to expand the rootfs to the full size of its partion, started as a systemd service which removes itself once finished"
+LICENSE = "Public Domain"
+PR = "r3"
+
+SRC_URI =  " \
+    file://resizefs.sh \
+    file://resizefs.service \
+    file://COPYING \
+"
+
+LIC_FILES_CHKSUM = "file://${WORKDIR}/COPYING;md5=1c3a7fb45253c11c74434676d84fe7dd"
+
+do_compile () {
+}
+
+do_install () {
+    install -d ${D}/${sbindir}
+    install -m 0755 ${WORKDIR}/*.sh ${D}/${sbindir}
+}
+
+NATIVE_SYSTEMD_SUPPORT = "1"
+SYSTEMD_PACKAGES = "${PN}"
+SYSTEMD_SERVICE_${PN} = "resizefs.service"
+
+inherit allarch systemd