| #! /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 <fdmanana@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 $tmp.* |
| } |
| |
| # get standard environment, filters and checks |
| . ./common/rc |
| . ./common/filter |
| |
| # real QA test starts here |
| _supported_fs btrfs |
| _supported_os Linux |
| _require_scratch |
| _require_cloner |
| |
| send_files_dir=$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 |
| |
| BLOCK_SIZE=$(_get_block_size $SCRATCH_MNT) |
| |
| # Create our test file with a single extent of 16 blocks starting at a file |
| # offset mapped by 32nd block. |
| $XFS_IO_PROG -f -c "pwrite -S 0xaa $((32 * $BLOCK_SIZE)) $((16 * $BLOCK_SIZE))" \ |
| $SCRATCH_MNT/foo | _filter_xfs_io_blocks_modified |
| |
| _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 4 blocks. The corresponding data back |
| # reference in the extent tree has a large value for the 'offset' field, which is |
| # the result of file_offset - data_offset = 0 - (file offset of 4th block). For |
| # example in case of 4k block size, it will be 0 - 16k = 18446744073709535232. |
| |
| # The second clone operation adds a file extent item to file offset mapped by |
| # 4th block that points to our initial extent with a data offset of 12 |
| # blocks. The corresponding data back reference in the extent tree has a large |
| # value for the 'offset' field, which is the result of file_offset - data_offset |
| # = (file offset of 4th block) - (file offset of 12th block). For example in |
| # case of 4k block size, it will be 16K - 48K = 18446744073709518848. |
| # |
| # 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 $(((32 + 4) * $BLOCK_SIZE)) -d 0 -l $((4 * $BLOCK_SIZE)) \ |
| $SCRATCH_MNT/foo $SCRATCH_MNT/foo |
| $CLONER_PROG -s $(((32 + 12) * $BLOCK_SIZE)) -d $((4 * $BLOCK_SIZE)) \ |
| -l $((4 * $BLOCK_SIZE)) $SCRATCH_MNT/foo $SCRATCH_MNT/foo |
| |
| _run_btrfs_util_prog subvolume snapshot -r $SCRATCH_MNT $SCRATCH_MNT/mysnap2 |
| |
| _run_btrfs_util_prog send -f $send_files_dir/1.snap $SCRATCH_MNT/mysnap1 |
| _run_btrfs_util_prog send -p $SCRATCH_MNT/mysnap1 -f $send_files_dir/2.snap \ |
| $SCRATCH_MNT/mysnap2 |
| |
| echo "File contents in the original filesystem:" |
| od -t x1 $SCRATCH_MNT/mysnap2/foo | _filter_od |
| |
| # Now recreate the filesystem by receiving both send streams and verify we get |
| # the same file contents that the original filesystem had. |
| _scratch_unmount |
| _scratch_mkfs >>$seqres.full 2>&1 |
| _scratch_mount |
| |
| _run_btrfs_util_prog receive -f $send_files_dir/1.snap $SCRATCH_MNT |
| _run_btrfs_util_prog receive -f $send_files_dir/2.snap $SCRATCH_MNT |
| |
| echo "File contents in the new filesystem:" |
| od -t x1 $SCRATCH_MNT/mysnap2/foo | _filter_od |
| |
| status=0 |
| exit |