[OE-core] [PATCH 2/2] init-live.sh: try to make a union mount when possible
Qi.Chen at windriver.com
Qi.Chen at windriver.com
Fri Jun 28 07:48:53 UTC 2013
From: Chen Qi <Qi.Chen at windriver.com>
This patch tries to make a union mount in live image. For example,
if aufs is enabled with the aufs-enable.scc configuration fragment,
the init-live.sh script will use aufs to make a union mount.
Although overlayfs is not supported by Yocto kernel yet, this patch
still takes it into consideration with the expect that the related
code should at least serve as a placeholder.
[YOCTO #1487]
[YOCTO #4761]
Signed-off-by: Chen Qi <Qi.Chen at windriver.com>
---
meta/recipes-core/initrdscripts/files/init-live.sh | 63 +++++++++++++++++---
1 file changed, 56 insertions(+), 7 deletions(-)
diff --git a/meta/recipes-core/initrdscripts/files/init-live.sh b/meta/recipes-core/initrdscripts/files/init-live.sh
index 00c2558..9804504 100644
--- a/meta/recipes-core/initrdscripts/files/init-live.sh
+++ b/meta/recipes-core/initrdscripts/files/init-live.sh
@@ -135,15 +135,64 @@ do
sleep 1
done
+# Try to make a union mount of the root image.
+# If no unification filesystem is available, mount the image read-only.
+mount_and_boot() {
+ mkdir $ROOT_MOUNT
+ mknod /dev/loop0 b 7 0 2>/dev/null
+
+ # determine which unification filesystem to use
+ union_fs_type=""
+ if grep -q -w "overlayfs" /proc/filesystems; then
+ union_fs_type="overlayfs"
+ elif grep -q -w "aufs" /proc/filesystems; then
+ union_fs_type="aufs"
+ else
+ union_fs_type=""
+ fi
+
+ # make a union mount if possible
+ case $union_fs_type in
+ "overlayfs")
+ mkdir -p /rootfs.ro /rootfs.rw
+ if ! mount -o rw,loop,noatime,nodiratime /media/$i/$ISOLINUX/$ROOT_IMAGE /rootfs.ro; then
+ rm -rf /rootfs.ro /rootfs.rw
+ fatal "Could not mount rootfs image"
+ else
+ mount -t tmpfs -o rw,noatime,mode=755 tmpfs /rootfs.rw
+ mount -t overlayfs -o "lowerdir=/rootfs.ro,upperdir=/rootfs.rw" overlayfs $ROOT_MOUNT
+ mkdir -p $ROOT_MOUNT/rootfs.ro $ROOT_MOUNT/rootfs.rw
+ mount --move /rootfs.ro $ROOT_MOUNT/rootfs.ro
+ mount --move /rootfs.rw $ROOT_MOUNT/rootfs.rw
+ fi
+ ;;
+ "aufs")
+ mkdir -p /rootfs.ro /rootfs.rw
+ if ! mount -o rw,loop,noatime,nodiratime /media/$i/$ISOLINUX/$ROOT_IMAGE /rootfs.ro; then
+ rm -rf /rootfs.ro /rootfs.rw
+ fatal "Could not mount rootfs image"
+ else
+ mount -t tmpfs -o rw,noatime,mode=755 tmpfs /rootfs.rw
+ mount -t aufs -o "dirs=/rootfs.rw=rw:/rootfs.ro=ro" aufs $ROOT_MOUNT
+ mkdir -p $ROOT_MOUNT/rootfs.ro $ROOT_MOUNT/rootfs.rw
+ mount --move /rootfs.ro $ROOT_MOUNT/rootfs.ro
+ mount --move /rootfs.rw $ROOT_MOUNT/rootfs.rw
+ fi
+ ;;
+ "")
+ if ! mount -o rw,loop,noatime,nodiratime /media/$i/$ISOLINUX/$ROOT_IMAGE $ROOT_MOUNT ; then
+ fatal "Could not mount rootfs image"
+ fi
+ ;;
+ esac
+
+ # boot the image
+ boot_live_root
+}
+
case $label in
boot)
- mkdir $ROOT_MOUNT
- mknod /dev/loop0 b 7 0 2>/dev/null
- if ! $MOUNT -o rw,loop,noatime,nodiratime /media/$i/$ISOLINUX/$ROOT_IMAGE $ROOT_MOUNT ; then
- fatal "Could not mount rootfs image"
- else
- boot_live_root
- fi
+ mount_and_boot
;;
install|install-efi)
if [ -f /media/$i/$ISOLINUX/$ROOT_IMAGE ] ; then
--
1.7.9.5
More information about the Openembedded-core
mailing list