generic/590: fix the xfs feature detection logic

The setup code in this regression test case tries to figure out if
certain features known to be incompatible with realtime are known to
mkfs, and if so, to forcibly disable them.

Unfortunately, the reflink feature detection logic here is broken,
because we have no way of distinguishing between the helper function
_scratch_mkfs_xfs_supported returning nonzero because reflink isn't
compatible with mkfs's defaults (e.g. your mkfs has rmapbt=1 by default)
vs. reflink isn't recognized at all vs. something else broke.

However, we can grep the mkfs output to look for reflink support, and if
we find it then we disable it.  That's fine for this test, since on XFS
it's trying to set up the exact conditions to test a known bug.

Second, rmapbt isn't currently compatible with realtime either, so we
need to detect and mask that off too.

Third, the test only needs to perform this feature detection if the test
runner didn't set SCRATCH_RTDEV, because we require that if the runner
configured SCRATCH_RTDEV, they also set MKFS_OPTIONS appropriately.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Eryu Guan <guaneryu@gmail.com>
Signed-off-by: Eryu Guan <guaneryu@gmail.com>
This commit is contained in:
Darrick J. Wong
2020-04-23 16:31:18 -07:00
committed by Eryu Guan
parent 10aa5e2904
commit 0f58b106e2
+26 -5
View File
@@ -41,6 +41,21 @@ bs=4096
rextsize=4
filesz=$(((maxextlen + 1) * bs))
must_disable_feature() {
local feat="$1"
# If mkfs doesn't know about the feature, we don't need to disable it
$MKFS_XFS_PROG --help 2>&1 | grep -q "${feat}=0" || return 1
# If turning the feature on works, we don't need to disable it
_scratch_mkfs_xfs_supported -m "${feat}=1" "${disabled_features[@]}" \
> /dev/null 2>&1 && return 1
# Otherwise mkfs knows of the feature and formatting with it failed,
# so we do need to mask it.
return 0
}
extra_options=""
# If we're testing XFS, set up the realtime device to reproduce the bug.
if [[ $FSTYP = xfs ]]; then
@@ -54,14 +69,20 @@ if [[ $FSTYP = xfs ]]; then
loop="$(_create_loop_device "$TEST_DIR/$seq")"
USE_EXTERNAL=yes
SCRATCH_RTDEV="$loop"
disabled_features=()
# disable reflink if not supported by realtime devices
must_disable_feature reflink &&
disabled_features=(-m reflink=0)
# disable rmap if not supported by realtime devices
must_disable_feature rmapbt &&
disabled_features+=(-m rmapbt=0)
fi
extra_options="$extra_options -r extsize=$((bs * rextsize))"
extra_options="$extra_options -d agsize=$(((maxextlen + 1) * bs / 2)),rtinherit=1"
# disable reflink as reflink not supported with realtime devices
if _scratch_mkfs_xfs_supported -m reflink=0 >/dev/null 2>&1; then
extra_options="$extra_options -m reflink=0"
fi
_scratch_mkfs $extra_options >>$seqres.full 2>&1
_scratch_mkfs $extra_options "${disabled_features[@]}" >>$seqres.full 2>&1
_try_scratch_mount >>$seqres.full 2>&1 || \
_notrun "mount failed, kernel doesn't support realtime?"
_scratch_unmount