blob: 441827b88fc68d1a2bf68be0b8cba59f6247c12f [file] [log] [blame]
#
# overlayfs specific common functions.
#
. ./common/module
# Export overlayfs xattrs and constant value
export OVL_XATTR_OPAQUE="trusted.overlay.opaque"
export OVL_XATTR_REDIRECT="trusted.overlay.redirect"
export OVL_XATTR_IMPURE="trusted.overlay.impure"
export OVL_XATTR_ORIGIN="trusted.overlay.origin"
export OVL_XATTR_NLINK="trusted.overlay.nlink"
export OVL_XATTR_UPPER="trusted.overlay.upper"
# helper function to do the actual overlayfs mount operation
_overlay_mount_dirs()
{
local lowerdir=$1
local upperdir=$2
local workdir=$3
shift 3
$MOUNT_PROG -t overlay -o lowerdir=$lowerdir -o upperdir=$upperdir \
-o workdir=$workdir `_common_dev_mount_options $*`
}
# Mount with same options/mnt/dev of scratch mount, but optionally
# with different lower/upper/work dirs
_overlay_scratch_mount_dirs()
{
local lowerdir=$1
local upperdir=$2
local workdir=$3
shift 3
_overlay_mount_dirs $lowerdir $upperdir $workdir \
$* $OVL_BASE_SCRATCH_MNT $SCRATCH_MNT
}
_overlay_mkdirs()
{
local dir=$1
mkdir -p $dir/$OVL_UPPER
mkdir -p $dir/$OVL_LOWER
mkdir -p $dir/$OVL_WORK
mkdir -p $dir/$OVL_MNT
}
# Given a base fs dir, set up overlay directories and mount on the given mnt.
# The dir is used as the mount device so it can be seen from df or mount
_overlay_mount()
{
local dir=$1
local mnt=$2
shift 2
_supports_filetype $dir || _notrun "upper fs needs to support d_type"
_overlay_mkdirs $dir
_overlay_mount_dirs $dir/$OVL_LOWER $dir/$OVL_UPPER $dir/$OVL_WORK \
$* $dir $mnt
}
_overlay_base_mount()
{
local devname=$1
local mntname=$2
local dev=$3
local mnt=$4
shift 4
if [ -z "$dev" -o -z "$mnt" ] || \
_check_mounted_on $devname $dev $mntname $mnt; then
# no base fs or already mounted
return 0
elif [ $? -ne 1 ]; then
# base fs mounted but not on mount point
return 1
fi
_mount $* $dev $mnt
}
_overlay_base_test_mount()
{
_overlay_base_mount OVL_BASE_TEST_DEV OVL_BASE_TEST_DIR \
"$OVL_BASE_TEST_DEV" "$OVL_BASE_TEST_DIR" \
$TEST_FS_MOUNT_OPTS $SELINUX_MOUNT_OPTIONS
}
_overlay_test_mount()
{
_overlay_base_test_mount && \
_overlay_mount $OVL_BASE_TEST_DIR $TEST_DIR $*
}
_overlay_base_scratch_mount()
{
_overlay_base_mount OVL_BASE_SCRATCH_DEV OVL_BASE_SCRATCH_MNT \
"$OVL_BASE_SCRATCH_DEV" "$OVL_BASE_SCRATCH_MNT" \
$OVL_BASE_MOUNT_OPTIONS $SELINUX_MOUNT_OPTIONS
}
_overlay_scratch_mount()
{
_overlay_base_scratch_mount && \
_overlay_mount $OVL_BASE_SCRATCH_MNT $SCRATCH_MNT $*
}
_overlay_base_unmount()
{
local dev=$1
local mnt=$2
[ -n "$dev" -a -n "$mnt" ] || return 0
$UMOUNT_PROG $mnt
}
_overlay_test_unmount()
{
$UMOUNT_PROG $TEST_DIR
_overlay_base_unmount "$OVL_BASE_TEST_DEV" "$OVL_BASE_TEST_DIR"
}
_overlay_scratch_unmount()
{
$UMOUNT_PROG $SCRATCH_MNT
_overlay_base_unmount "$OVL_BASE_SCRATCH_DEV" "$OVL_BASE_SCRATCH_MNT"
}
# Check that a specific overlayfs feature is supported
__check_scratch_overlay_feature()
{
local feature=$1
# overalyfs features (e.g. redirect_dir, index) are
# configurable from Kconfig (the build default), by module
# parameter (the system default) and per mount by mount
# option ${feature}=[on|off].
#
# If the module parameter does not exist then there is no
# point in checking the mount option.
local default=`_get_fs_module_param ${feature}`
[ "$default" = Y ] || [ "$default" = N ] || \
_notrun "feature '${feature}' not supported by ${FSTYP}"
# Check options to be sure. For example, Overlayfs will fallback to
# index=off if underlying fs does not support file handles.
# Overlayfs only displays mount option if it differs from the default.
# Overlayfs may enable the feature, but fallback to read-only mount.
((( [ "$default" = N ] && _fs_options $SCRATCH_DEV | grep -q "${feature}=on" ) || \
( [ "$default" = Y ] && ! _fs_options $SCRATCH_DEV | grep -q "${feature}=off" )) && \
touch $SCRATCH_MNT/foo 2>/dev/null ) || \
_notrun "${FSTYP} feature '${feature}' cannot be enabled on ${SCRATCH_DEV}"
}
# Require a set of overlayfs features
_require_scratch_overlay_features()
{
local features=( $* )
local opts="rw"
for feature in ${features[*]}; do
opts+=",${feature}=on"
done
_scratch_mkfs > /dev/null 2>&1
_try_scratch_mount -o $opts || \
_notrun "overlay options '$opts' cannot be enabled on ${SCRATCH_DEV}"
for feature in ${features[*]}; do
__check_scratch_overlay_feature ${feature}
done
_scratch_unmount
}
# Helper function to check underlying dirs of overlay filesystem
_overlay_fsck_dirs()
{
local lowerdir=$1
local upperdir=$2
local workdir=$3
shift 3
[[ ! -x "$FSCK_OVERLAY_PROG" ]] && return 0
$FSCK_OVERLAY_PROG -o lowerdir=$lowerdir -o upperdir=$upperdir \
-o workdir=$workdir $*
}
_overlay_check_dirs()
{
local lowerdir=$1
local upperdir=$2
local workdir=$3
shift 3
local err=0
_overlay_fsck_dirs $lowerdir $upperdir $workdir \
$FSCK_OPTIONS $* >>$tmp.fsck 2>&1
if [ $? -ne 0 ]; then
_log_err "_overlay_check_fs: overlayfs on $lowerdir,$upperdir,$workdir is inconsistent"
echo "*** fsck.overlay output ***" >>$seqres.full
cat $tmp.fsck >>$seqres.full
echo "*** end fsck.overlay output" >>$seqres.full
echo "*** mount output ***" >>$seqres.full
_mount >>$seqres.full
echo "*** end mount output" >>$seqres.full
err=1
fi
rm -f $tmp.fsck
return $err
}
# Check the same mnt/dev of _check_overlay_scratch_fs but non-default
# underlying scratch dirs of overlayfs, it needs lower/upper/work dirs
# provided as arguments, and it's useful for non-default setups such
# as multiple lower layers
_overlay_check_scratch_dirs()
{
local lowerdir=$1
local upperdir=$2
local workdir=$3
shift 3
# Need to umount overlay for scratch dir check
local ovl_mounted=`_is_dir_mountpoint $SCRATCH_MNT`
[ -z "$ovl_mounted" ] || $UMOUNT_PROG $SCRATCH_MNT
# Check dirs with extra overlay options
_overlay_check_dirs $lowerdir $upperdir $workdir $*
local ret=$?
if [ $ret -eq 0 -a -n "$ovl_mounted" ]; then
# overlay was mounted, remount with extra mount options
_overlay_scratch_mount_dirs $lowerdir $upperdir \
$workdir $*
ret=$?
fi
return $ret
}
_overlay_check_fs()
{
# The first arguments is overlay mount point use for checking
# overlay filesystem is mounted or not, the remaining arquments
# use for mounting overlay base filesystem if it was not mounted.
# We shift one to aligns arguments for _overlay_base_mount.
local ovl_mnt=$1
shift 1
local base_dev=$3
local base_mnt=$4
[ "$FSTYP" = overlay ] || return 0
# Base fs needs to be mounted to check overlay dirs
local base_fstype=""
local ovl_mounted=""
[ -z "$base_dev" ] || \
base_fstype=`_fs_type $base_dev`
# If base_dev is set but base_fstype is empty, base fs is not
# mounted, we need to mount base fs. Otherwise, we need to
# check and umount overlayfs if it was mounted.
if [ -n "$base_dev" -a -z "$base_fstype" ]; then
_overlay_base_mount $*
else
# Check and umount overlay for dir check
ovl_mounted=`_is_dir_mountpoint $ovl_mnt`
[ -z "$ovl_mounted" ] || $UMOUNT_PROG $ovl_mnt
fi
_overlay_check_dirs $base_mnt/$OVL_LOWER $base_mnt/$OVL_UPPER \
$base_mnt/$OVL_WORK
local ret=$?
if [ -n "$base_dev" -a -z "$base_fstype" ]; then
_overlay_base_unmount "$base_dev" "$base_mnt"
elif [ $ret -eq 0 -a -n "$ovl_mounted" ]; then
# overlay was mounted, remount besides extra mount options
_overlay_mount $base_mnt $ovl_mnt
ret=$?
fi
if [ $ret != 0 ]; then
status=1
if [ "$iam" != "check" ]; then
exit 1
fi
return 1
fi
return 0
}
_check_overlay_test_fs()
{
_overlay_check_fs "$TEST_DIR" \
OVL_BASE_TEST_DEV OVL_BASE_TEST_DIR \
"$OVL_BASE_TEST_DEV" "$OVL_BASE_TEST_DIR" \
$TEST_FS_MOUNT_OPTS $SELINUX_MOUNT_OPTIONS
}
_check_overlay_scratch_fs()
{
_overlay_check_fs "$SCRATCH_MNT" \
OVL_BASE_SCRATCH_DEV OVL_BASE_SCRATCH_MNT \
"$OVL_BASE_SCRATCH_DEV" "$OVL_BASE_SCRATCH_MNT" \
$OVL_BASE_MOUNT_OPTIONS $SELINUX_MOUNT_OPTIONS
}