From a7fdd2e1b1dc028faf021223d3d550a593689b96 Mon Sep 17 00:00:00 2001 From: Filipe Manana Date: Tue, 20 Oct 2020 15:43:01 +0100 Subject: [PATCH] btrfs: add test case for rwf_nowait writes Test several scenarios for RWF_NOWAIT writes, to verify we don't regress on btrfs specific behaviour (snapshots, cow files, reflinks, holes, prealloc extent beyond eof). We had some bugs in the past related to RWF_NOWAIT writes not failing on btrfs when they should or failing when they shouldn't, these were fixed by the following kernel commits: 4b1946284dd6 ("btrfs: fix failure of RWF_NOWAIT write into prealloc extent beyond eof") 260a63395f90 ("btrfs: fix RWF_NOWAIT write not failling when we need to cow") Signed-off-by: Filipe Manana Reviewed-by: Josef Bacik Signed-off-by: Eryu Guan --- tests/btrfs/226 | 140 ++++++++++++++++++++++++++++++++++++++++++++ tests/btrfs/226.out | 70 ++++++++++++++++++++++ tests/btrfs/group | 1 + 3 files changed, 211 insertions(+) create mode 100755 tests/btrfs/226 create mode 100644 tests/btrfs/226.out diff --git a/tests/btrfs/226 b/tests/btrfs/226 new file mode 100755 index 00000000..c523cf4a --- /dev/null +++ b/tests/btrfs/226 @@ -0,0 +1,140 @@ +#! /bin/bash +# SPDX-License-Identifier: GPL-2.0 +# Copyright (C) 2020 SUSE Linux Products GmbH. All Rights Reserved. +# +# FS QA Test No. btrfs/226 +# +# Test several (btrfs specific) scenarios with RWF_NOWAIT writes, cases where +# they should fail and cases where they should succeed. +# +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() +{ + cd / + rm -f $tmp.* +} + +# get standard environment, filters and checks +. ./common/rc +. ./common/filter +. ./common/reflink + +# real QA test starts here +_supported_fs btrfs +_require_scratch_reflink +_require_chattr C +_require_odirect +_require_xfs_io_command pwrite -N +_require_xfs_io_command falloc -k +_require_xfs_io_command fpunch + +rm -f $seqres.full + +_scratch_mkfs >>$seqres.full 2>&1 +_scratch_mount + +# Test a write against COW file/extent - should fail with -EAGAIN. Disable the +# NOCOW attribute of the file just in case MOUNT_OPTIONS has "-o nodatacow". +echo "Testing write against COW file" +touch $SCRATCH_MNT/f1 +$CHATTR_PROG -C $SCRATCH_MNT/f1 +$XFS_IO_PROG -s -c "pwrite -S 0xab 0 128K" $SCRATCH_MNT/f1 | _filter_xfs_io +$XFS_IO_PROG -d -c "pwrite -N -V 1 -S 0xff 32K 64K" $SCRATCH_MNT/f1 + +# Check no data was written. +echo "File data after write attempt:" +od -A d -t x1 $SCRATCH_MNT/f1 + +# Create a file with two extents (NOCOW), then create a snapshot, unshare the +# first extent by writing to it without RWF_NOWAIT, and then attempt to write +# to a file range that includes both the non-shared and the shared extent - +# should fail with -EAGAIN. +echo +echo "Testing write against extent shared across snapshots" +touch $SCRATCH_MNT/f2 +$CHATTR_PROG +C $SCRATCH_MNT/f2 +$XFS_IO_PROG -s -c "pwrite -S 0xab 0 64K" \ + -c "pwrite -S 0xcd 64K 64K" \ + $SCRATCH_MNT/f2 | _filter_xfs_io + +$BTRFS_UTIL_PROG subvolume snapshot $SCRATCH_MNT $SCRATCH_MNT/snap \ + | _filter_scratch + +# Write into the range of the first extent so that that range no longer has a +# shared extent. +$XFS_IO_PROG -s -c "pwrite -S 0xab 0 64K" $SCRATCH_MNT/f2 | _filter_xfs_io + +# Attempt to write into the file range, using RWF_NOWAIT, that covers the +# non-shared and the shared extents, should fail. +$XFS_IO_PROG -d -c "pwrite -N -V 1 -S 0xff -b 64K 32K 64K" $SCRATCH_MNT/f2 + +# Check no data was written. +echo "File data after write attempt:" +od -A d -t x1 $SCRATCH_MNT/f2 + +# Create a file that has an extent shared with file f2. Attempting to write +# into a range that covers the shared extent should fail with -EAGAIN. +echo +echo "Testing write against shared extent through reflink" +touch $SCRATCH_MNT/f3 +$CHATTR_PROG +C $SCRATCH_MNT/f3 +$XFS_IO_PROG -s -c "pwrite -S 0xab -b 64K 0 64K" \ + -c "reflink $SCRATCH_MNT/f2 64K 64K 64K" \ + $SCRATCH_MNT/f3 | _filter_xfs_io + +# Should fail, range 64K to 96K has a shared extent. +$XFS_IO_PROG -d -c "pwrite -N -V 1 -S 0xff -b 64K 32K 64K" $SCRATCH_MNT/f3 + +# Check no data was written. +echo "File data after write attempt:" +od -A d -t x1 $SCRATCH_MNT/f3 + +# Create a file with a prealloc extent at eof and attempt to write to it, it +# should succeed. +echo +echo "Testing write against prealloc extent at eof" +$XFS_IO_PROG -f -s -c "pwrite -S 0xab 0 64K" \ + -c "falloc -k 64K 64K" \ + $SCRATCH_MNT/f4 | _filter_xfs_io + +# Should succeed. +$XFS_IO_PROG -d -c "pwrite -N -V 1 -S 0xcd -b 64K 64K 64K" $SCRATCH_MNT/f4 \ + | _filter_xfs_io + +# Check the file has the expected data. +echo "File after write:" +od -A d -t x1 $SCRATCH_MNT/f4 + +# Attempts to write to ranges that have a hole, should fail with -EAGAIN. +echo +echo "Testing writes against ranges with holes" +touch $SCRATCH_MNT/f5 +$CHATTR_PROG +C $SCRATCH_MNT/f5 +# 3 64Kb extents, with a 64K hole at offset 128K. +$XFS_IO_PROG -s -d -c "pwrite -S 0xab -b 64K 0 64K" \ + -s -d -c "pwrite -S 0xcd -b 64K 64K 64K" \ + -s -d -c "pwrite -S 0xef -b 64K 192K 64K" \ + $SCRATCH_MNT/f5 | _filter_xfs_io + +# Should fail, second half of the range maps to a hole. +$XFS_IO_PROG -d -c "pwrite -N -V 1 -S 0x11 -b 128K 64K 128K" $SCRATCH_MNT/f5 + +# Now try with a range that starts with a hole and ends with an extent, should +# fail as well. +$XFS_IO_PROG -c "fpunch 0 64K" \ + -d -c "pwrite -N -V 1 -S 0x22 -b 128K 0 128K" \ + $SCRATCH_MNT/f5 + +# Check no data was written. +echo "File data after write attempt:" +od -A d -t x1 $SCRATCH_MNT/f5 + +status=0 +exit diff --git a/tests/btrfs/226.out b/tests/btrfs/226.out new file mode 100644 index 00000000..c63982b0 --- /dev/null +++ b/tests/btrfs/226.out @@ -0,0 +1,70 @@ +QA output created by 226 +Testing write against COW file +wrote 131072/131072 bytes at offset 0 +XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec) +pwrite: Resource temporarily unavailable +File data after write attempt: +0000000 ab ab ab ab ab ab ab ab ab ab ab ab ab ab ab ab +* +0131072 + +Testing write against extent shared across snapshots +wrote 65536/65536 bytes at offset 0 +XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec) +wrote 65536/65536 bytes at offset 65536 +XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec) +Create a snapshot of 'SCRATCH_MNT' in 'SCRATCH_MNT/snap' +wrote 65536/65536 bytes at offset 0 +XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec) +pwrite: Resource temporarily unavailable +File data after write attempt: +0000000 ab ab ab ab ab ab ab ab ab ab ab ab ab ab ab ab +* +0065536 cd cd cd cd cd cd cd cd cd cd cd cd cd cd cd cd +* +0131072 + +Testing write against shared extent through reflink +wrote 65536/65536 bytes at offset 0 +XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec) +linked 65536/65536 bytes at offset 65536 +XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec) +pwrite: Resource temporarily unavailable +File data after write attempt: +0000000 ab ab ab ab ab ab ab ab ab ab ab ab ab ab ab ab +* +0065536 cd cd cd cd cd cd cd cd cd cd cd cd cd cd cd cd +* +0131072 + +Testing write against prealloc extent at eof +wrote 65536/65536 bytes at offset 0 +XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec) +wrote 65536/65536 bytes at offset 65536 +XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec) +File after write: +0000000 ab ab ab ab ab ab ab ab ab ab ab ab ab ab ab ab +* +0065536 cd cd cd cd cd cd cd cd cd cd cd cd cd cd cd cd +* +0131072 + +Testing writes against ranges with holes +wrote 65536/65536 bytes at offset 0 +XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec) +wrote 65536/65536 bytes at offset 65536 +XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec) +wrote 65536/65536 bytes at offset 196608 +XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec) +pwrite: Resource temporarily unavailable +pwrite: Resource temporarily unavailable +File data after write attempt: +0000000 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 +* +0065536 cd cd cd cd cd cd cd cd cd cd cd cd cd cd cd cd +* +0131072 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 +* +0196608 ef ef ef ef ef ef ef ef ef ef ef ef ef ef ef ef +* +0262144 diff --git a/tests/btrfs/group b/tests/btrfs/group index 960981e5..d18450c7 100644 --- a/tests/btrfs/group +++ b/tests/btrfs/group @@ -227,3 +227,4 @@ 223 auto quick replace trim 224 auto quick qgroup 225 auto quick volume seed +226 auto quick rw snapshot clone prealloc punch -- 2.30.2