2 # overlayfs specific common functions.
6 # Export overlayfs xattrs and constant value
7 export OVL_XATTR_OPAQUE="trusted.overlay.opaque"
8 export OVL_XATTR_REDIRECT="trusted.overlay.redirect"
9 export OVL_XATTR_IMPURE="trusted.overlay.impure"
10 export OVL_XATTR_ORIGIN="trusted.overlay.origin"
11 export OVL_XATTR_NLINK="trusted.overlay.nlink"
12 export OVL_XATTR_UPPER="trusted.overlay.upper"
13 export OVL_XATTR_METACOPY="trusted.overlay.metacopy"
15 # helper function to do the actual overlayfs mount operation
23 $MOUNT_PROG -t overlay -o lowerdir=$lowerdir -o upperdir=$upperdir \
24 -o workdir=$workdir `_common_dev_mount_options $*`
27 # Mount with same options/mnt/dev of scratch mount, but optionally
28 # with different lower/upper/work dirs
29 _overlay_scratch_mount_dirs()
36 _overlay_mount_dirs $lowerdir $upperdir $workdir \
37 $* $OVL_BASE_SCRATCH_MNT $SCRATCH_MNT
44 mkdir -p $dir/$OVL_UPPER
45 mkdir -p $dir/$OVL_LOWER
46 mkdir -p $dir/$OVL_WORK
47 mkdir -p $dir/$OVL_MNT
50 # Given a base fs dir, set up overlay directories and mount on the given mnt.
51 # The dir is used as the mount device so it can be seen from df or mount
58 _supports_filetype $dir || _notrun "upper fs needs to support d_type"
62 _overlay_mount_dirs $dir/$OVL_LOWER $dir/$OVL_UPPER $dir/$OVL_WORK \
74 if [ -z "$dev" -o -z "$mnt" ] || \
75 _check_mounted_on $devname $dev $mntname $mnt; then
76 # no base fs or already mounted
78 elif [ $? -ne 1 ]; then
79 # base fs mounted but not on mount point
86 _overlay_base_test_mount()
88 _overlay_base_mount OVL_BASE_TEST_DEV OVL_BASE_TEST_DIR \
89 "$OVL_BASE_TEST_DEV" "$OVL_BASE_TEST_DIR" \
90 $TEST_FS_MOUNT_OPTS $SELINUX_MOUNT_OPTIONS
95 _overlay_base_test_mount && \
96 _overlay_mount $OVL_BASE_TEST_DIR $TEST_DIR $*
99 _overlay_base_scratch_mount()
101 _overlay_base_mount OVL_BASE_SCRATCH_DEV OVL_BASE_SCRATCH_MNT \
102 "$OVL_BASE_SCRATCH_DEV" "$OVL_BASE_SCRATCH_MNT" \
103 $OVL_BASE_MOUNT_OPTIONS $SELINUX_MOUNT_OPTIONS
106 _overlay_scratch_mount()
108 _overlay_base_scratch_mount && \
109 _overlay_mount $OVL_BASE_SCRATCH_MNT $SCRATCH_MNT $*
112 _overlay_base_unmount()
117 [ -n "$dev" -a -n "$mnt" ] || return 0
122 _overlay_test_unmount()
124 $UMOUNT_PROG $TEST_DIR
125 _overlay_base_unmount "$OVL_BASE_TEST_DEV" "$OVL_BASE_TEST_DIR"
128 _overlay_scratch_unmount()
130 $UMOUNT_PROG $SCRATCH_MNT
131 _overlay_base_unmount "$OVL_BASE_SCRATCH_DEV" "$OVL_BASE_SCRATCH_MNT"
134 # Check that a specific overlayfs feature is supported
135 __check_scratch_overlay_feature()
139 # overalyfs features (e.g. redirect_dir, index) are
140 # configurable from Kconfig (the build default), by module
141 # parameter (the system default) and per mount by mount
142 # option ${feature}=[on|off].
144 # If the module parameter does not exist then there is no
145 # point in checking the mount option.
146 local default=`_get_fs_module_param ${feature}`
147 [ "$default" = Y ] || [ "$default" = N ] || \
148 _notrun "feature '${feature}' not supported by ${FSTYP}"
150 # Check options to be sure. For example, Overlayfs will fallback to
151 # index=off if underlying fs does not support file handles.
152 # Overlayfs only displays mount option if it differs from the default.
153 # Overlayfs may enable the feature, but fallback to read-only mount.
154 ((( [ "$default" = N ] && _fs_options $SCRATCH_DEV | grep -q "${feature}=on" ) || \
155 ( [ "$default" = Y ] && ! _fs_options $SCRATCH_DEV | grep -q "${feature}=off" )) && \
156 touch $SCRATCH_MNT/foo 2>/dev/null ) || \
157 _notrun "${FSTYP} feature '${feature}' cannot be enabled on ${SCRATCH_DEV}"
160 # Require a set of overlayfs features
161 _require_scratch_overlay_features()
163 local features=( $* )
166 for feature in ${features[*]}; do
167 opts+=",${feature}=on"
170 _scratch_mkfs > /dev/null 2>&1
171 _try_scratch_mount -o $opts || \
172 _notrun "overlay options '$opts' cannot be enabled on ${SCRATCH_DEV}"
174 for feature in ${features[*]}; do
175 __check_scratch_overlay_feature ${feature}
181 # Helper function to check underlying dirs of overlay filesystem
189 [[ ! -x "$FSCK_OVERLAY_PROG" ]] && return 0
191 $FSCK_OVERLAY_PROG -o lowerdir=$lowerdir -o upperdir=$upperdir \
192 -o workdir=$workdir $*
195 _overlay_check_dirs()
203 _overlay_fsck_dirs $lowerdir $upperdir $workdir \
204 $FSCK_OPTIONS $* >>$tmp.fsck 2>&1
205 if [ $? -ne 0 ]; then
206 _log_err "_overlay_check_fs: overlayfs on $lowerdir,$upperdir,$workdir is inconsistent"
208 echo "*** fsck.overlay output ***" >>$seqres.full
209 cat $tmp.fsck >>$seqres.full
210 echo "*** end fsck.overlay output" >>$seqres.full
212 echo "*** mount output ***" >>$seqres.full
213 _mount >>$seqres.full
214 echo "*** end mount output" >>$seqres.full
223 # Check the same mnt/dev of _check_overlay_scratch_fs but non-default
224 # underlying scratch dirs of overlayfs, it needs lower/upper/work dirs
225 # provided as arguments, and it's useful for non-default setups such
226 # as multiple lower layers
227 _overlay_check_scratch_dirs()
234 # Need to umount overlay for scratch dir check
235 local ovl_mounted=`_is_dir_mountpoint $SCRATCH_MNT`
236 [ -z "$ovl_mounted" ] || $UMOUNT_PROG $SCRATCH_MNT
238 # Check dirs with extra overlay options
239 _overlay_check_dirs $lowerdir $upperdir $workdir $*
242 if [ $ret -eq 0 -a -n "$ovl_mounted" ]; then
243 # overlay was mounted, remount with extra mount options
244 _overlay_scratch_mount_dirs $lowerdir $upperdir \
254 # The first arguments is overlay mount point use for checking
255 # overlay filesystem is mounted or not, the remaining arquments
256 # use for mounting overlay base filesystem if it was not mounted.
257 # We shift one to aligns arguments for _overlay_base_mount.
264 [ "$FSTYP" = overlay ] || return 0
266 # Base fs needs to be mounted to check overlay dirs
270 [ -z "$base_dev" ] || \
271 base_fstype=`_fs_type $base_dev`
273 # If base_dev is set but base_fstype is empty, base fs is not
274 # mounted, we need to mount base fs. Otherwise, we need to
275 # check and umount overlayfs if it was mounted.
276 if [ -n "$base_dev" -a -z "$base_fstype" ]; then
277 _overlay_base_mount $*
279 # Check and umount overlay for dir check
280 ovl_mounted=`_is_dir_mountpoint $ovl_mnt`
281 [ -z "$ovl_mounted" ] || $UMOUNT_PROG $ovl_mnt
284 _overlay_check_dirs $base_mnt/$OVL_LOWER $base_mnt/$OVL_UPPER \
288 if [ -n "$base_dev" -a -z "$base_fstype" ]; then
289 _overlay_base_unmount "$base_dev" "$base_mnt"
290 elif [ $ret -eq 0 -a -n "$ovl_mounted" ]; then
291 # overlay was mounted, remount besides extra mount options
292 _overlay_mount $base_mnt $ovl_mnt
296 if [ $ret != 0 ]; then
298 if [ "$iam" != "check" ]; then
307 _check_overlay_test_fs()
309 _overlay_check_fs "$TEST_DIR" \
310 OVL_BASE_TEST_DEV OVL_BASE_TEST_DIR \
311 "$OVL_BASE_TEST_DEV" "$OVL_BASE_TEST_DIR" \
312 $TEST_FS_MOUNT_OPTS $SELINUX_MOUNT_OPTIONS
315 _check_overlay_scratch_fs()
317 _overlay_check_fs "$SCRATCH_MNT" \
318 OVL_BASE_SCRATCH_DEV OVL_BASE_SCRATCH_MNT \
319 "$OVL_BASE_SCRATCH_DEV" "$OVL_BASE_SCRATCH_MNT" \
320 $OVL_BASE_MOUNT_OPTIONS $SELINUX_MOUNT_OPTIONS