diff mbox

fstests: sanity check that test partitions are not mounted elsewhere

Message ID 1486746385-5364-1-git-send-email-amir73il@gmail.com (mailing list archive)
State New, archived
Headers show

Commit Message

Amir Goldstein Feb. 10, 2017, 5:06 p.m. UTC
When $TEST_DEV is mounted at a different location than $TEST_DIR,
_require_test() aborts the test with an error:
 TEST_DEV=/dev/sda5 is mounted but not on TEST_DIR=/mnt/test

There are several problems with current sanity check:
1. the output of the error is mixed into out.bad and hard to see
2. the test partition is unmounted at the end of the test regardless
   of the fact that it not pass the sanity that we have exclusivity
3. scratch partition has a similar sanity check in _require_scratch(),
   but we may not get to it, because $SCRATCH_DEV is unmounted prior
   to running the tests (which could unmount another mount point).

To solve all these problems, introduce a helper _check_mounted_on().
It checks if a device is mounted on a given mount point and optionally
checks the mounted fs type.

The sanity checks in _require_scratch() and _require_test() are
converted to use the _check_mounted_on() helper.

The helper is used in init_rc() to sanity check both test and scratch
partitions, before tests are run and before $SCRATCH_DEV is unmounted.

Signed-off-by: Amir Goldstein <amir73il@gmail.com>
---
 common/rc | 85 ++++++++++++++++++++++++++++++++++++++-------------------------
 1 file changed, 51 insertions(+), 34 deletions(-)

Eryu,

As result of your request to add sanity checks to overlay base fs, I ended
up finding several bugs in current sanity checks (not overlay related).

So sending this one out because it is useful on its own. Overlay base fs
patches are going to be on top of this change and use the helper as well.

Incidently, this change also fixes an overlay setup bug, but I did not
want to add this info to the already overloaded commit message, as the
following base fs patches will make this bug obsolete -
If you configure SCRATCH_DEV to a mount point (and not to a directory therein)
then you will get a false positive error in scratch tests:

 $SCRATCH_DEV=/mnt/base/scratch is mounted but not on $SCRATCH_MNT=/mnt/scratch
 Already mounted result:
 /dev/sda6 on /mnt/base/scratch type xfs (rw,relatime,attr2,inode64,noquota)

This is due to the wrong `grep -F $SCRATCH_DEV` which matches the mount
point instead of the device in that mount.
I am pretty sure we already has this discussion where you changed the pattern
to `grep -F ^$dev` and I advised you to go with `grep -F "$dev on "`. Anyway,
this change includes this fix.

Amir.
diff mbox

Patch

diff --git a/common/rc b/common/rc
index 7e2eaee..1c773cc 100644
--- a/common/rc
+++ b/common/rc
@@ -1319,6 +1319,45 @@  _supported_os()
     _notrun "not suitable for this OS: $HOSTOS"
 }
 
+# check if a FS on a device is mounted
+# if so, verify that it is mounted on mount point
+# if fstype is given as argument, verify that it is also
+# mounted with correct fs type
+#
+_check_mounted_on()
+{
+	local devname=$1
+	local dev=$2
+	local mntname=$3
+	local mnt=$4
+	local type=$5
+
+	# Note that we use -F here so grep doesn't try to interpret an NFS over
+	# IPv6 server as a regular expression.  Because of that, we cannot use
+	# ^$dev so we use "$dev on " to avoid matching $dev to mount point field
+	# for overlay case, where $dev is a directory.
+	local mount_rec=`_mount | grep -F "$dev on "`
+	[ -n "$mount_rec" ] || return 1
+
+	# if it's mounted, make sure its on $mnt
+	if ! (echo $mount_rec | grep -q "$dev on $mnt")
+	then
+		echo "$devname=$dev is mounted but not on $mntname=$mnt - aborting"
+		echo "Already mounted result:"
+		echo $mount_rec
+		exit 1
+	fi
+
+	if [ -n "$type" -a "`_fs_type $dev`" != "$type" ]
+	then
+		echo "$devname=$dev is mounted but not a type $type filesystem"
+		# raw $DF_PROG cannot handle NFS/CIFS/overlay correctly
+		_df_device $dev
+		exit 1
+	fi
+	return 0
+}
+
 # this test needs a scratch partition - check we're ok & unmount it
 # No post-test check of the device is required. e.g. the test intentionally
 # finishes the test with the filesystem in a corrupt state
@@ -1373,21 +1412,9 @@  _require_scratch_nocheck()
 		 ;;
     esac
 
-    # mounted?
-    # Note that we use -F here so grep doesn't try to interpret an NFS over
-    # IPv6 server as a regular expression.
-    mount_rec=`_mount | grep -F $SCRATCH_DEV`
-    if [ "$mount_rec" ]
+    if _check_mounted_on SCRATCH_DEV $SCRATCH_DEV SCRATCH_MNT $SCRATCH_MNT
     then
-        # if it's mounted, make sure its on $SCRATCH_MNT
-        if ! echo $mount_rec | grep -q $SCRATCH_MNT
-        then
-            echo "\$SCRATCH_DEV=$SCRATCH_DEV is mounted but not on \$SCRATCH_MNT=$SCRATCH_MNT - aborting"
-            echo "Already mounted result:"
-            echo $mount_rec
-            exit 1
-        fi
-        # and then unmount it
+        # if it's mounted, unmount it
         if ! _scratch_unmount
         then
             echo "failed to unmount $SCRATCH_DEV"
@@ -1458,21 +1485,8 @@  _require_test()
 		 ;;
     esac
 
-    # mounted?
-    # Note that we use -F here so grep doesn't try to interpret an NFS over
-    # IPv6 server as a regular expression.
-    mount_rec=`_mount | grep -F $TEST_DEV`
-    if [ "$mount_rec" ]
+    if ! _check_mounted_on TEST_DEV $TEST_DEV TEST_DIR $TEST_DIR
     then
-        # if it's mounted, make sure its on $TEST_DIR
-        if ! echo $mount_rec | grep -q $TEST_DIR
-        then
-            echo "\$TEST_DEV=$TEST_DEV is mounted but not on \$TEST_DIR=$TEST_DIR - aborting"
-            echo "Already mounted result:"
-            echo $mount_rec
-            exit 1
-        fi
-    else
 	out=`_mount_or_remount_rw "$MOUNT_OPTIONS" $TEST_DEV $TEST_DIR`
 	if [ $? -ne 1 ]; then
 		echo $out
@@ -3066,13 +3080,16 @@  init_rc()
 		fi
 	fi
 
-	if [ "`_fs_type $TEST_DEV`" != "$FSTYP" ]
-	then
-		echo "common/rc: Error: \$TEST_DEV ($TEST_DEV) is not a MOUNTED $FSTYP filesystem"
-		# raw $DF_PROG cannot handle NFS/CIFS/overlay correctly
-		_df_device $TEST_DEV
-		exit 1
+	# Sanity check that TEST partition is not mounted at another mount point
+	# or as another fs type
+	_check_mounted_on TEST_DEV $TEST_DEV TEST_DIR $TEST_DIR $FSTYP
+	if [ -n "$SCRATCH_DEV" ]; then
+		# Sanity check that SCRATCH partition is not mounted at another
+		# mount point, because it is about to be unmounted and formatted.
+		# Another fs type for scratch is fine (bye bye old fs type).
+		_check_mounted_on SCRATCH_DEV $SCRATCH_DEV SCRATCH_MNT $SCRATCH_MNT
 	fi
+
 	# Figure out if we need to add -F ("foreign", deprecated) option to xfs_io
 	$XFS_IO_PROG -c stat $TEST_DIR 2>&1 | grep -q "is not on an XFS filesystem" && \
 		export XFS_IO_PROG="$XFS_IO_PROG -F"