From: Filipe Manana <fdman...@suse.com> Test that an incremental send works after a file gets one of its extents cloned/deduplicated into lower file offsets.
This is a regression test for the problem fixed by the linux kernel patch titled: "Btrfs: teach backref walking about backrefs with underflowed offset values" Signed-off-by: Filipe Manana <fdman...@suse.com> --- tests/btrfs/097 | 113 ++++++++++++++++++++++++++++++++++++++++++++++++++++ tests/btrfs/097.out | 7 ++++ tests/btrfs/group | 1 + 3 files changed, 121 insertions(+) create mode 100755 tests/btrfs/097 create mode 100644 tests/btrfs/097.out diff --git a/tests/btrfs/097 b/tests/btrfs/097 new file mode 100755 index 0000000..d9138ea --- /dev/null +++ b/tests/btrfs/097 @@ -0,0 +1,113 @@ +#! /bin/bash +# FS QA Test No. btrfs/097 +# +# Test that an incremental send works after a file gets one of its extents +# cloned/deduplicated into lower file offsets. +# +#----------------------------------------------------------------------- +# Copyright (C) 2015 SUSE Linux Products GmbH. All Rights Reserved. +# Author: Filipe Manana <fdman...@suse.com> +# +# This program is free software; you can redistribute it and/or +# modify it under the terms of the GNU General Public License as +# published by the Free Software Foundation. +# +# This program is distributed in the hope that it would be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU General Public License for more details. +# +# You should have received a copy of the GNU General Public License +# along with this program; if not, write the Free Software Foundation, +# Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA +#----------------------------------------------------------------------- +# + +seq=`basename $0` +seqres=$RESULT_DIR/$seq +echo "QA output created by $seq" + +tmp=/tmp/$$ +status=1 # failure is the default! +trap "_cleanup; exit \$status" 0 1 2 3 15 + +_cleanup() +{ + rm -fr $send_files_dir + rm -f $tmp.* +} + +# get standard environment, filters and checks +. ./common/rc +. ./common/filter + +# real QA test starts here +_supported_fs btrfs +_supported_os Linux +_require_scratch +_require_cloner +_need_to_be_root + +send_files_dir=$TEST_DIR/btrfs-test-$seq + +rm -f $seqres.full +rm -fr $send_files_dir +mkdir $send_files_dir + +_scratch_mkfs >>$seqres.full 2>&1 +_scratch_mount + +# Create our test file with a single extent of 64K starting at file offset 128K. +$XFS_IO_PROG -f -c "pwrite -S 0xaa 128K 64K" $SCRATCH_MNT/foo | _filter_xfs_io + +_run_btrfs_util_prog subvolume snapshot -r $SCRATCH_MNT $SCRATCH_MNT/mysnap1 + +# Now clone parts of the original extent into lower offsets of the file. +# +# The first clone operation adds a file extent item to file offset 0 that points +# to our initial extent with a data offset of 16K. The corresponding data back +# reference in the extent tree has an offset of 18446744073709535232, which is +# the result of file_offset - data_offset = 0 - 16K. +# +# The second clone operation adds a file extent item to file offset 16K that +# points to our initial extent with a data offset of 48K. The corresponding data +# back reference in the extent tree has an offset of 18446744073709518848, which +# is the result of file_offset - data_offset = 16K - 48K. +# +# Those large back reference offsets (result of unsigned arithmetic underflow) +# confused the back reference walking code (used by an incremental send and +# the multiple inspect-internal ioctls) and made it miss the back references, +# which for the case of an incremental send it made it fail with -EIO and print +# a message like the following to dmesg: +# +# "BTRFS error (device sdc): did not find backref in send_root. inode=257, \ +# offset=0, disk_byte=12845056 found extent=12845056" +# +$CLONER_PROG -s $(((128 + 16) * 1024)) -d 0 -l $((16 * 1024)) \ + $SCRATCH_MNT/foo $SCRATCH_MNT/foo +$CLONER_PROG -s $(((128 + 48) * 1024)) -d $((16 * 1024)) -l $((16 * 1024)) \ + $SCRATCH_MNT/foo $SCRATCH_MNT/foo + +_run_btrfs_util_prog subvolume snapshot -r $SCRATCH_MNT $SCRATCH_MNT/mysnap2 + +_run_btrfs_util_prog send $SCRATCH_MNT/mysnap1 -f $send_files_dir/1.snap +_run_btrfs_util_prog send -p $SCRATCH_MNT/mysnap1 $SCRATCH_MNT/mysnap2 \ + -f $send_files_dir/2.snap + +echo "File digest in the original filesystem:" +md5sum $SCRATCH_MNT/mysnap2/foo | _filter_scratch + +# Now recreate the filesystem by receiving both send streams and verify we get +# the same file contents that the original filesystem had. +_scratch_unmount +_scratch_mkfs >>$seqres.full 2>&1 +_scratch_mount + +_run_btrfs_util_prog receive $SCRATCH_MNT -f $send_files_dir/1.snap +_run_btrfs_util_prog receive $SCRATCH_MNT -f $send_files_dir/2.snap + +echo "File digest in the new filesystem:" +md5sum $SCRATCH_MNT/mysnap2/foo | _filter_scratch + +status=0 +exit diff --git a/tests/btrfs/097.out b/tests/btrfs/097.out new file mode 100644 index 0000000..5e87eb2 --- /dev/null +++ b/tests/btrfs/097.out @@ -0,0 +1,7 @@ +QA output created by 097 +wrote 65536/65536 bytes at offset 131072 +XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec) +File digest in the original filesystem: +6c6079335cff141b8a31233ead04cbff SCRATCH_MNT/mysnap2/foo +File digest in the new filesystem: +6c6079335cff141b8a31233ead04cbff SCRATCH_MNT/mysnap2/foo diff --git a/tests/btrfs/group b/tests/btrfs/group index 6ff5f3d..39700c0 100644 --- a/tests/btrfs/group +++ b/tests/btrfs/group @@ -98,3 +98,4 @@ 094 auto quick send 095 auto quick metadata 096 auto quick clone +097 auto quick send clone -- 2.1.3 -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html