| #! /bin/bash |
| # SPDX-License-Identifier: GPL-2.0 |
| # Copyright (c) 2017 Red Hat Inc. All Rights Reserved. |
| # |
| # FS QA Test 460 |
| # |
| # Test that XFS reserves reasonable indirect blocks for delalloc and |
| # speculative allocation, and doesn't cause any fdblocks corruption. |
| # |
| # This was inspired by an XFS but that too large 'indlen' was returned by |
| # xfs_bmap_worst_indlen() which can't fit in a 17 bits value (STARTBLOCKVALBITS |
| # is defined as 17), then leaked 1 << 17 blocks in sb_fdblocks. |
| # |
| # This was only seen on XFS with rmapbt feature enabled, but nothing prevents |
| # the test from being a generic test. |
| # |
| seq=`basename $0` |
| seqres=$RESULT_DIR/$seq |
| echo "QA output created by $seq" |
| |
| here=`pwd` |
| tmp=/tmp/$$ |
| status=1 # failure is the default! |
| testfile=$SCRATCH_MNT/1G_file.$seq |
| file_size=$((1024 * 1024 * 1024)) |
| trap "_cleanup; exit \$status" 0 1 2 3 15 |
| |
| saved_dirty_background_ratio=0 |
| saved_dirty_ratio=0 |
| |
| save_dirty_ratio() |
| { |
| saved_dirty_background_ratio=`cat /proc/sys/vm/dirty_background_ratio` |
| saved_dirty_ratio=`cat /proc/sys/vm/dirty_ratio` |
| } |
| |
| set_dirty_ratio() |
| { |
| echo 100 > /proc/sys/vm/dirty_background_ratio |
| echo 100 > /proc/sys/vm/dirty_ratio |
| } |
| |
| restore_dirty_ratio() |
| { |
| if [ $saved_dirty_background_ratio -ne 0 ]; then |
| echo $saved_dirty_background_ratio > /proc/sys/vm/dirty_background_ratio |
| fi |
| if [ $saved_dirty_ratio -ne 0 ]; then |
| echo $saved_dirty_ratio > /proc/sys/vm/dirty_ratio |
| fi |
| } |
| |
| _cleanup() |
| { |
| cd / |
| restore_dirty_ratio |
| rm -f $tmp.* |
| } |
| |
| # get standard environment, filters and checks |
| . ./common/rc |
| . ./common/filter |
| |
| # remove previous $seqres.full before test |
| rm -f $seqres.full |
| |
| # real QA test starts here |
| _supported_fs generic |
| # test with scratch device, because test is known to corrupt fs, we don't want |
| # the corruption affect subsequent tests |
| _require_scratch |
| |
| _scratch_mkfs >>$seqres.full 2>&1 |
| _scratch_mount |
| |
| # need at least 1G free space |
| _require_fs_space $SCRATCH_MNT $((1024 * 1024)) |
| |
| # To reproduce the bug, we need to keep enough dirty data in memory (1G at |
| # least), so that a large enough delay allocated extent is kept in memory, then |
| # speculative preallocation could allocate large number of blocks based on the |
| # existing extent size. |
| # So we set dirty_background_ratio and dirty_ratio to 100% uncontitionally, |
| # even if the total memory is less than 1G, there's no harm to run a test on a |
| # such host. |
| save_dirty_ratio |
| set_dirty_ratio |
| |
| # buffer write a 1G file, which is enough to trigger the bug, |
| # _check_filesystems will complain about fs corruption after test |
| $XFS_IO_PROG -fc "pwrite -b 1m 0 $file_size" $testfile >/dev/null 2>&1 |
| |
| echo "Silence is golden" |
| |
| # success, all done |
| status=0 |
| exit |