On Wed, Nov 02, 2022 at 03:36:21PM -0700, Darrick J. Wong wrote:
> From: Darrick J. Wong <djwong@xxxxxxxxxx>
>
> Add new helpers to dmerror to provide for marking selected ranges
> totally bad -- both reads and writes will fail. Create a new test for
> xfs_scrub to check that it reports media errors in data files correctly.
>
> Signed-off-by: Darrick J. Wong <djwong@xxxxxxxxxx>
> ---
> common/dmerror | 140 ++++++++++++++++++++++++++++++++++++++++++++++++
> common/xfs | 9 +++
> tests/xfs/747 | 155 +++++++++++++++++++++++++++++++++++++++++++++++++++++
> tests/xfs/747.out | 12 ++++
> 4 files changed, 316 insertions(+)
> create mode 100755 tests/xfs/747
> create mode 100644 tests/xfs/747.out
>
>
> diff --git a/common/dmerror b/common/dmerror
> index 54122b12ea..ca71fc11b4 100644
> --- a/common/dmerror
> +++ b/common/dmerror
> @@ -250,3 +250,143 @@ _dmerror_load_working_table()
> [ $load_res -ne 0 ] && _fail "dmsetup failed to load error table"
> [ $resume_res -ne 0 ] && _fail "dmsetup resume failed"
> }
> +
> +# Given a list of (start, length) tuples on stdin, combine adjacent tuples into
> +# larger ones and write the new list to stdout.
> +__dmerror_combine_extents()
> +{
> + awk 'BEGIN{start = 0; len = 0;}{
> +if (start + len == $1) {
> + len += $2;
> +} else {
> + if (len > 0)
> + printf("%d %d\n", start, len);
> + start = $1;
> + len = $2;
> +}
> +} END {
> + if (len > 0)
> + printf("%d %d\n", start, len);
> +}'
> +}
> +
> +# Given a block device, the name of a preferred dm target, the name of an
> +# implied dm target, and a list of (start, len) tuples on stdin, create a new
> +# dm table which maps each of the tuples to the preferred target and all other
> +# areas to the implied dm target.
> +__dmerror_recreate_map()
> +{
> + local device="$1"
> + local preferred_tgt="$2"
> + local implied_tgt="$3"
> + local size=$(blockdev --getsz "$device")
> +
> + local awk_program='
> + BEGIN {
> + implied_start = 0;
> + }
> + {
> + extent_start = $1;
> + extent_len = $2;
> +
> + if (extent_start > size) {
> + extent_start = size;
> + extent_len = 0;
> + } else if (extent_start + extent_len > size) {
> + extent_len = size - extent_start;
> + }
> +
> + if (implied_start < extent_start)
> + printf("%d %d %s %s %d\n", implied_start,
> + extent_start - implied_start,
> + implied_tgt, device, implied_start);
> + printf("%d %d %s %s %d\n", extent_start, extent_len,
> + preferred_tgt, device, extent_start);
> + implied_start = extent_start + extent_len;
> + }
> + END {
> + if (implied_start < size)
> + printf("%d %d %s %s %d\n", implied_start,
> + size - implied_start, implied_tgt,
> + device, implied_start);
> + }'
> +
> + awk -v device="$device" -v size=$size -v implied_tgt="$implied_tgt" \
> + -v preferred_tgt="$preferred_tgt" "$awk_program"
Hi,
OK, if you prefer this way, should __dmerror_combine_extents follow this way too :)
> +}
> +
> +# Update the dm error table so that the range (start, len) maps to the
> +# preferred dm target, overriding anything that maps to the implied dm target.
> +# This assumes that the only desired targets for this dm device are the
> +# preferred and and implied targets. The fifth argument is the scratch device
> +# that we want to change the table for.
> +__dmerror_change()
> +{
> + local start="$1"
> + local len="$2"
> + local preferred_tgt="$3"
> + local implied_tgt="$4"
> + local whichdev="$5"
> + local old_table
> + local new_table
> +
> + case "$whichdev" in
> + "SCRATCH_DEV"|"") whichdev="$SCRATCH_DEV";;
> + "SCRATCH_LOGDEV"|"LOG") whichdev="$NON_ERROR_LOGDEV";;
> + "SCRATCH_RTDEV"|"RT") whichdev="$NON_ERROR_RTDEV";;
> + esac
> +
> + case "$whichdev" in
> + "$SCRATCH_DEV") old_table="$DMERROR_TABLE";;
> + "$NON_ERROR_LOGDEV") old_table="$DMERROR_LOGTABLE";;
> + "$NON_ERROR_RTDEV") old_table="$DMERROR_RTTABLE";;
> + *)
> + echo "$whichdev: Unknown dmerror device."
> + return
> + ;;
> + esac
> +
> + new_table="$( (echo "$old_table"; echo "$start $len $preferred_tgt") | \
> + awk -v type="$preferred_tgt" '{if ($3 == type) print $0;}' | \
> + sort -g | \
> + __dmerror_combine_extents | \
> + __dmerror_recreate_map "$whichdev" "$preferred_tgt" \
> + "$implied_tgt" )"
> +
> + case "$whichdev" in
> + "$SCRATCH_DEV") DMERROR_TABLE="$new_table";;
> + "$NON_ERROR_LOGDEV") DMERROR_LOGTABLE="$new_table";;
> + "$NON_ERROR_RTDEV") DMERROR_RTTABLE="$new_table";;
> + esac
> +}
> +
> +# Reset the dm error table to everything ok. The dm device itself must be
> +# remapped by calling _dmerror_load_error_table.
> +_dmerror_reset_table()
> +{
> + DMERROR_TABLE="$DMLINEAR_TABLE"
> + DMERROR_LOGTABLE="$DMLINEAR_LOGTABLE"
> + DMERROR_RTTABLE="$DMLINEAR_RTTABLE"
> +}
> +
> +# Update the dm error table so that IOs to the given range will return EIO.
> +# The dm device itself must be remapped by calling _dmerror_load_error_table.
> +_dmerror_mark_range_bad()
> +{
> + local start="$1"
> + local len="$2"
> + local dev="$3"
> +
> + __dmerror_change "$start" "$len" error linear "$dev"
> +}
> +
> +# Update the dm error table so that IOs to the given range will succeed.
> +# The dm device itself must be remapped by calling _dmerror_load_error_table.
> +_dmerror_mark_range_good()
> +{
> + local start="$1"
> + local len="$2"
> + local dev="$3"
> +
> + __dmerror_change "$start" "$len" linear error "$dev"
> +}
> diff --git a/common/xfs b/common/xfs
> index 8ac1964e9c..f466d2c42f 100644
> --- a/common/xfs
> +++ b/common/xfs
> @@ -218,6 +218,15 @@ _xfs_get_dir_blocksize()
> $XFS_INFO_PROG "$fs" | sed -n "s/^naming.*bsize=\([[:digit:]]*\).*/\1/p"
> }
>
> +# Decide if this path is a file on the realtime device
> +_xfs_is_realtime_file()
> +{
> + if [ "$USE_EXTERNAL" != "yes" ] || [ -z "$SCRATCH_RTDEV" ]; then
> + return 1
> + fi
> + $XFS_IO_PROG -c 'stat -v' "$1" | grep -q -w realtime
> +}
> +
> # Set or clear the realtime status of every supplied path. The first argument
> # is either 'data' or 'realtime'. All other arguments should be paths to
> # existing directories or empty regular files.
> diff --git a/tests/xfs/747 b/tests/xfs/747
> new file mode 100755
> index 0000000000..8b828bc48d
> --- /dev/null
> +++ b/tests/xfs/747
> @@ -0,0 +1,155 @@
> +#! /bin/bash
> +# SPDX-License-Identifier: GPL-2.0-or-later
> +# Copyright (c) 2022 Oracle. All Rights Reserved.
> +#
> +# FS QA Test No. 747
> +#
> +# Check xfs_scrub's media scan can actually return diagnostic information for
> +# media errors in file data extents.
> +
> +. ./common/preamble
> +_begin_fstest auto quick scrub
Do we need "eio" at here?
Others look good to me.
Thanks,
Zorro
> +
> +# Override the default cleanup function.
> +_cleanup()
> +{
> + cd /
> + rm -f $tmp.*
> + _dmerror_cleanup
> +}
> +
> +# Import common functions.
> +. ./common/fuzzy
> +. ./common/filter
> +. ./common/dmerror
> +
> +# real QA test starts here
> +_supported_fs xfs
> +_require_dm_target error
> +_require_scratch
> +_require_scratch_xfs_crc
> +_require_scrub
> +
> +filter_scrub_errors() {
> + _filter_scratch | sed \
> + -e "s/offset $((fs_blksz * 2)) /offset 2FSB /g" \
> + -e "s/length $fs_blksz.*/length 1FSB./g"
> +}
> +
> +_scratch_mkfs >> $seqres.full
> +_dmerror_init
> +_dmerror_mount >> $seqres.full 2>&1
> +
> +_supports_xfs_scrub $SCRATCH_MNT $SCRATCH_DEV || _notrun "Scrub not supported"
> +
> +# Write a file with 4 file blocks worth of data
> +victim=$SCRATCH_MNT/a
> +file_blksz=$(_get_file_block_size $SCRATCH_MNT)
> +$XFS_IO_PROG -f -c "pwrite -S 0x58 0 $((4 * file_blksz))" -c "fsync" $victim >> $seqres.full
> +unset errordev
> +_xfs_is_realtime_file $victim && errordev="RT"
> +bmap_str="$($XFS_IO_PROG -c "bmap -elpv" $victim | grep "^[[:space:]]*0:")"
> +echo "$errordev:$bmap_str" >> $seqres.full
> +
> +phys="$(echo "$bmap_str" | $AWK_PROG '{print $3}')"
> +if [ "$errordev" = "RT" ]; then
> + len="$(echo "$bmap_str" | $AWK_PROG '{print $4}')"
> +else
> + len="$(echo "$bmap_str" | $AWK_PROG '{print $6}')"
> +fi
> +fs_blksz=$(_get_block_size $SCRATCH_MNT)
> +echo "file_blksz:$file_blksz:fs_blksz:$fs_blksz" >> $seqres.full
> +kernel_sectors_per_fs_block=$((fs_blksz / 512))
> +
> +# Did we get at least 4 fs blocks worth of extent?
> +min_len_sectors=$(( 4 * kernel_sectors_per_fs_block ))
> +test "$len" -lt $min_len_sectors && \
> + _fail "could not format a long enough extent on an empty fs??"
> +
> +phys_start=$(echo "$phys" | sed -e 's/\.\..*//g')
> +
> +echo "$errordev:$phys:$len:$fs_blksz:$phys_start" >> $seqres.full
> +echo "victim file:" >> $seqres.full
> +od -tx1 -Ad -c $victim >> $seqres.full
> +
> +# Set the dmerror table so that all IO will pass through.
> +_dmerror_reset_table
> +
> +cat >> $seqres.full << ENDL
> +dmerror before:
> +$DMERROR_TABLE
> +$DMERROR_RTTABLE
> +<end table>
> +ENDL
> +
> +# All sector numbers that we feed to the kernel must be in units of 512b, but
> +# they also must be aligned to the device's logical block size.
> +logical_block_size=$(_min_dio_alignment $SCRATCH_DEV)
> +kernel_sectors_per_device_lba=$((logical_block_size / 512))
> +
> +# Mark as bad one of the device LBAs in the middle of the extent. Target the
> +# second LBA of the third block of the four-block file extent that we allocated
> +# earlier, but without overflowing into the fourth file block.
> +bad_sector=$(( phys_start + (2 * kernel_sectors_per_fs_block) ))
> +bad_len=$kernel_sectors_per_device_lba
> +if (( kernel_sectors_per_device_lba < kernel_sectors_per_fs_block )); then
> + bad_sector=$((bad_sector + kernel_sectors_per_device_lba))
> +fi
> +if (( (bad_sector % kernel_sectors_per_device_lba) != 0)); then
> + echo "bad_sector $bad_sector not congruent with device logical block size $logical_block_size"
> +fi
> +_dmerror_mark_range_bad $bad_sector $bad_len $errordev
> +
> +cat >> $seqres.full << ENDL
> +dmerror after marking bad:
> +$DMERROR_TABLE
> +$DMERROR_RTTABLE
> +<end table>
> +ENDL
> +
> +_dmerror_load_error_table
> +
> +# See if the media scan picks it up.
> +echo "Scrub for injected media error (single threaded)"
> +
> +# Once in single-threaded mode
> +_scratch_scrub -b -x >> $seqres.full 2> $tmp.error
> +cat $tmp.error | filter_scrub_errors
> +
> +# Once in parallel mode
> +echo "Scrub for injected media error (multi threaded)"
> +_scratch_scrub -x >> $seqres.full 2> $tmp.error
> +cat $tmp.error | filter_scrub_errors
> +
> +# Remount to flush the page cache and reread to see the IO error
> +_dmerror_unmount
> +_dmerror_mount
> +echo "victim file:" >> $seqres.full
> +od -tx1 -Ad -c $victim >> $seqres.full 2> $tmp.error
> +cat $tmp.error | sed -e 's/read error: //g' | _filter_scratch
> +
> +# Scrub again to re-confirm the media error across a remount
> +echo "Scrub for injected media error (after remount)"
> +_scratch_scrub -x >> $seqres.full 2> $tmp.error
> +cat $tmp.error | filter_scrub_errors
> +
> +# Now mark the bad range good so that a retest shows no media failure.
> +_dmerror_mark_range_good $bad_sector $bad_len $errordev
> +_dmerror_load_error_table
> +
> +cat >> $seqres.full << ENDL
> +dmerror after marking good:
> +$DMERROR_TABLE
> +$DMERROR_RTTABLE
> +<end table>
> +ENDL
> +
> +echo "Scrub after removing injected media error"
> +
> +# Scrub one last time to make sure the error's gone.
> +_scratch_scrub -x >> $seqres.full 2> $tmp.error
> +cat $tmp.error | filter_scrub_errors
> +
> +# success, all done
> +status=0
> +exit
> diff --git a/tests/xfs/747.out b/tests/xfs/747.out
> new file mode 100644
> index 0000000000..714ceb2e56
> --- /dev/null
> +++ b/tests/xfs/747.out
> @@ -0,0 +1,12 @@
> +QA output created by 747
> +Scrub for injected media error (single threaded)
> +Unfixable Error: SCRATCH_MNT/a: media error at data offset 2FSB length 1FSB.
> +SCRATCH_MNT: unfixable errors found: 1
> +Scrub for injected media error (multi threaded)
> +Unfixable Error: SCRATCH_MNT/a: media error at data offset 2FSB length 1FSB.
> +SCRATCH_MNT: unfixable errors found: 1
> +od: SCRATCH_MNT/a: Input/output error
> +Scrub for injected media error (after remount)
> +Unfixable Error: SCRATCH_MNT/a: media error at data offset 2FSB length 1FSB.
> +SCRATCH_MNT: unfixable errors found: 1
> +Scrub after removing injected media error
>
