* [PATCH] fstests: add a another gap extent testcase for btrfs
@ 2020-02-20 14:38 Josef Bacik
2020-02-20 16:24 ` Filipe Manana
0 siblings, 1 reply; 4+ messages in thread
From: Josef Bacik @ 2020-02-20 14:38 UTC (permalink / raw)
To: linux-btrfs, kernel-team, fstests
This is a testcase for a corner that I missed when trying to fix gap
extents for btrfs. We would end up with gaps if we hole punched past
isize and then extended past the gap in a specific way. This is a
simple reproducer to show the problem, and has been properly fixed by my
patches now.
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
---
tests/btrfs/204 | 85 +++++++++++++++++++++++++++++++++++++++++++++
tests/btrfs/204.out | 5 +++
tests/btrfs/group | 1 +
3 files changed, 91 insertions(+)
create mode 100755 tests/btrfs/204
create mode 100644 tests/btrfs/204.out
diff --git a/tests/btrfs/204 b/tests/btrfs/204
new file mode 100755
index 00000000..0d5c4bed
--- /dev/null
+++ b/tests/btrfs/204
@@ -0,0 +1,85 @@
+#! /bin/bash
+# SPDX-License-Identifier: GPL-2.0
+# Copyright (c) 2020 Facebook. All Rights Reserved.
+#
+# FS QA Test 204
+#
+# Validate that without no-holes we do not get a i_size that is after a gap in
+# the file extents on disk when punching a hole past i_size. This is fixed by
+# the following patches
+#
+# btrfs: use the file extent tree infrastructure
+# btrfs: replace all uses of btrfs_ordered_update_i_size
+#
+seq=`basename $0`
+seqres=$RESULT_DIR/$seq
+echo "QA output created by $seq"
+
+here=`pwd`
+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/dmlogwrites
+
+# remove previous $seqres.full before test
+rm -f $seqres.full
+
+# real QA test starts here
+
+# Modify as appropriate.
+_supported_fs generic
+_supported_os Linux
+_require_test
+_require_scratch
+_require_log_writes
+
+_log_writes_init $SCRATCH_DEV
+_log_writes_mkfs "-O ^no-holes" >> $seqres.full 2>&1
+
+# There's not a straightforward way to commit the transaction without also
+# flushing dirty pages, so shorten the commit interval to 1 so we're sure to get
+# a commit with our broken file
+_log_writes_mount -o commit=1
+
+# This creates a gap extent because fpunch doesn't insert hole extents past
+# i_size
+xfs_io -f -c "falloc -k 4k 8k" $SCRATCH_MNT/file
+xfs_io -f -c "fpunch 4k 4k" $SCRATCH_MNT/file
+
+# The pwrite extends the i_size to cover the gap extent, and then the truncate
+# sets the disk_i_size to 12k because it assumes everything was a-ok.
+xfs_io -f -c "pwrite 0 4k" $SCRATCH_MNT/file | _filter_xfs_io
+xfs_io -f -c "pwrite 0 8k" $SCRATCH_MNT/file | _filter_xfs_io
+xfs_io -f -c "truncate 12k" $SCRATCH_MNT/file
+
+# Wait for a transaction commit
+sleep 2
+
+_log_writes_unmount
+_log_writes_remove
+
+cur=$(_log_writes_find_next_fua 0)
+echo "cur=$cur" >> $seqres.full
+while [ ! -z "$cur" ]; do
+ _log_writes_replay_log_range $cur $SCRATCH_DEV >> $seqres.full
+
+ # We only care about the fs consistency, so just run fsck, we don't have
+ # to mount the fs to validate it
+ _check_scratch_fs
+
+ cur=$(_log_writes_find_next_fua $(($cur + 1)))
+done
+
+# success, all done
+status=0
+exit
diff --git a/tests/btrfs/204.out b/tests/btrfs/204.out
new file mode 100644
index 00000000..44c7c8ae
--- /dev/null
+++ b/tests/btrfs/204.out
@@ -0,0 +1,5 @@
+QA output created by 204
+wrote 4096/4096 bytes at offset 0
+XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
+wrote 8192/8192 bytes at offset 0
+XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
diff --git a/tests/btrfs/group b/tests/btrfs/group
index 6acc6426..7a840177 100644
--- a/tests/btrfs/group
+++ b/tests/btrfs/group
@@ -206,3 +206,4 @@
201 auto quick punch log
202 auto quick subvol snapshot
203 auto quick send clone
+204 auto quick log replay
--
2.24.1
^ permalink raw reply related [flat|nested] 4+ messages in thread
* Re: [PATCH] fstests: add a another gap extent testcase for btrfs
2020-02-20 14:38 [PATCH] fstests: add a another gap extent testcase for btrfs Josef Bacik
@ 2020-02-20 16:24 ` Filipe Manana
2020-02-20 17:12 ` Josef Bacik
2020-02-23 14:54 ` Eryu Guan
0 siblings, 2 replies; 4+ messages in thread
From: Filipe Manana @ 2020-02-20 16:24 UTC (permalink / raw)
To: Josef Bacik; +Cc: linux-btrfs, kernel-team, fstests
On Thu, Feb 20, 2020 at 2:39 PM Josef Bacik <josef@toxicpanda.com> wrote:
>
> This is a testcase for a corner that I missed when trying to fix gap
> extents for btrfs. We would end up with gaps if we hole punched past
> isize and then extended past the gap in a specific way. This is a
> simple reproducer to show the problem, and has been properly fixed by my
> patches now.
>
> Signed-off-by: Josef Bacik <josef@toxicpanda.com>
> ---
> tests/btrfs/204 | 85 +++++++++++++++++++++++++++++++++++++++++++++
> tests/btrfs/204.out | 5 +++
> tests/btrfs/group | 1 +
> 3 files changed, 91 insertions(+)
> create mode 100755 tests/btrfs/204
> create mode 100644 tests/btrfs/204.out
>
> diff --git a/tests/btrfs/204 b/tests/btrfs/204
> new file mode 100755
> index 00000000..0d5c4bed
> --- /dev/null
> +++ b/tests/btrfs/204
> @@ -0,0 +1,85 @@
> +#! /bin/bash
> +# SPDX-License-Identifier: GPL-2.0
> +# Copyright (c) 2020 Facebook. All Rights Reserved.
> +#
> +# FS QA Test 204
> +#
> +# Validate that without no-holes we do not get a i_size that is after a gap in
> +# the file extents on disk when punching a hole past i_size. This is fixed by
> +# the following patches
> +#
> +# btrfs: use the file extent tree infrastructure
> +# btrfs: replace all uses of btrfs_ordered_update_i_size
> +#
> +seq=`basename $0`
> +seqres=$RESULT_DIR/$seq
> +echo "QA output created by $seq"
> +
> +here=`pwd`
> +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/dmlogwrites
> +
> +# remove previous $seqres.full before test
> +rm -f $seqres.full
> +
> +# real QA test starts here
> +
> +# Modify as appropriate.
> +_supported_fs generic
> +_supported_os Linux
> +_require_test
> +_require_scratch
> +_require_log_writes
_require_xfs_io_command "falloc" "-k"
_require_xfs_io_command "fpunch"
> +
> +_log_writes_init $SCRATCH_DEV
> +_log_writes_mkfs "-O ^no-holes" >> $seqres.full 2>&1
> +
> +# There's not a straightforward way to commit the transaction without also
> +# flushing dirty pages, so shorten the commit interval to 1 so we're sure to get
> +# a commit with our broken file
> +_log_writes_mount -o commit=1
> +
> +# This creates a gap extent because fpunch doesn't insert hole extents past
> +# i_size
> +xfs_io -f -c "falloc -k 4k 8k" $SCRATCH_MNT/file
> +xfs_io -f -c "fpunch 4k 4k" $SCRATCH_MNT/file
> +
> +# The pwrite extends the i_size to cover the gap extent, and then the truncate
> +# sets the disk_i_size to 12k because it assumes everything was a-ok.
> +xfs_io -f -c "pwrite 0 4k" $SCRATCH_MNT/file | _filter_xfs_io
> +xfs_io -f -c "pwrite 0 8k" $SCRATCH_MNT/file | _filter_xfs_io
> +xfs_io -f -c "truncate 12k" $SCRATCH_MNT/file
> +
> +# Wait for a transaction commit
> +sleep 2
> +
> +_log_writes_unmount
> +_log_writes_remove
> +
> +cur=$(_log_writes_find_next_fua 0)
> +echo "cur=$cur" >> $seqres.full
> +while [ ! -z "$cur" ]; do
> + _log_writes_replay_log_range $cur $SCRATCH_DEV >> $seqres.full
> +
> + # We only care about the fs consistency, so just run fsck, we don't have
> + # to mount the fs to validate it
> + _check_scratch_fs
> +
> + cur=$(_log_writes_find_next_fua $(($cur + 1)))
> +done
> +
> +# success, all done
> +status=0
> +exit
> diff --git a/tests/btrfs/204.out b/tests/btrfs/204.out
> new file mode 100644
> index 00000000..44c7c8ae
> --- /dev/null
> +++ b/tests/btrfs/204.out
> @@ -0,0 +1,5 @@
> +QA output created by 204
> +wrote 4096/4096 bytes at offset 0
> +XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
> +wrote 8192/8192 bytes at offset 0
> +XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
> diff --git a/tests/btrfs/group b/tests/btrfs/group
> index 6acc6426..7a840177 100644
> --- a/tests/btrfs/group
> +++ b/tests/btrfs/group
> @@ -206,3 +206,4 @@
> 201 auto quick punch log
> 202 auto quick subvol snapshot
> 203 auto quick send clone
> +204 auto quick log replay
"prealloc" and "punch" groups as well.
Since this just tests another variant of the same problem, maybe it
could be added to btrfs/172, since that test is very recent and you
authored it as well.
Anyway, I don't have a strong preference.
The test itself looks good to me, and with the _require_xfs_io_command
thing added and the groups (maybe Eryu can add these at commit time):
Reviewed-by: Filipe Manana <fdmanana@suse.com>
> --
> 2.24.1
>
--
Filipe David Manana,
“Whether you think you can, or you think you can't — you're right.”
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [PATCH] fstests: add a another gap extent testcase for btrfs
2020-02-20 16:24 ` Filipe Manana
@ 2020-02-20 17:12 ` Josef Bacik
2020-02-23 14:54 ` Eryu Guan
1 sibling, 0 replies; 4+ messages in thread
From: Josef Bacik @ 2020-02-20 17:12 UTC (permalink / raw)
To: fdmanana; +Cc: linux-btrfs, kernel-team, fstests
On 2/20/20 11:24 AM, Filipe Manana wrote:
> On Thu, Feb 20, 2020 at 2:39 PM Josef Bacik <josef@toxicpanda.com> wrote:
>>
>> This is a testcase for a corner that I missed when trying to fix gap
>> extents for btrfs. We would end up with gaps if we hole punched past
>> isize and then extended past the gap in a specific way. This is a
>> simple reproducer to show the problem, and has been properly fixed by my
>> patches now.
>>
>> Signed-off-by: Josef Bacik <josef@toxicpanda.com>
>> ---
>> tests/btrfs/204 | 85 +++++++++++++++++++++++++++++++++++++++++++++
>> tests/btrfs/204.out | 5 +++
>> tests/btrfs/group | 1 +
>> 3 files changed, 91 insertions(+)
>> create mode 100755 tests/btrfs/204
>> create mode 100644 tests/btrfs/204.out
>>
>> diff --git a/tests/btrfs/204 b/tests/btrfs/204
>> new file mode 100755
>> index 00000000..0d5c4bed
>> --- /dev/null
>> +++ b/tests/btrfs/204
>> @@ -0,0 +1,85 @@
>> +#! /bin/bash
>> +# SPDX-License-Identifier: GPL-2.0
>> +# Copyright (c) 2020 Facebook. All Rights Reserved.
>> +#
>> +# FS QA Test 204
>> +#
>> +# Validate that without no-holes we do not get a i_size that is after a gap in
>> +# the file extents on disk when punching a hole past i_size. This is fixed by
>> +# the following patches
>> +#
>> +# btrfs: use the file extent tree infrastructure
>> +# btrfs: replace all uses of btrfs_ordered_update_i_size
>> +#
>> +seq=`basename $0`
>> +seqres=$RESULT_DIR/$seq
>> +echo "QA output created by $seq"
>> +
>> +here=`pwd`
>> +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/dmlogwrites
>> +
>> +# remove previous $seqres.full before test
>> +rm -f $seqres.full
>> +
>> +# real QA test starts here
>> +
>> +# Modify as appropriate.
>> +_supported_fs generic
>> +_supported_os Linux
>> +_require_test
>> +_require_scratch
>> +_require_log_writes
>
> _require_xfs_io_command "falloc" "-k"
> _require_xfs_io_command "fpunch"
>
>> +
>> +_log_writes_init $SCRATCH_DEV
>> +_log_writes_mkfs "-O ^no-holes" >> $seqres.full 2>&1
>> +
>> +# There's not a straightforward way to commit the transaction without also
>> +# flushing dirty pages, so shorten the commit interval to 1 so we're sure to get
>> +# a commit with our broken file
>> +_log_writes_mount -o commit=1
>> +
>> +# This creates a gap extent because fpunch doesn't insert hole extents past
>> +# i_size
>> +xfs_io -f -c "falloc -k 4k 8k" $SCRATCH_MNT/file
>> +xfs_io -f -c "fpunch 4k 4k" $SCRATCH_MNT/file
>> +
>> +# The pwrite extends the i_size to cover the gap extent, and then the truncate
>> +# sets the disk_i_size to 12k because it assumes everything was a-ok.
>> +xfs_io -f -c "pwrite 0 4k" $SCRATCH_MNT/file | _filter_xfs_io
>> +xfs_io -f -c "pwrite 0 8k" $SCRATCH_MNT/file | _filter_xfs_io
>> +xfs_io -f -c "truncate 12k" $SCRATCH_MNT/file
>> +
>> +# Wait for a transaction commit
>> +sleep 2
>> +
>> +_log_writes_unmount
>> +_log_writes_remove
>> +
>> +cur=$(_log_writes_find_next_fua 0)
>> +echo "cur=$cur" >> $seqres.full
>> +while [ ! -z "$cur" ]; do
>> + _log_writes_replay_log_range $cur $SCRATCH_DEV >> $seqres.full
>> +
>> + # We only care about the fs consistency, so just run fsck, we don't have
>> + # to mount the fs to validate it
>> + _check_scratch_fs
>> +
>> + cur=$(_log_writes_find_next_fua $(($cur + 1)))
>> +done
>> +
>> +# success, all done
>> +status=0
>> +exit
>> diff --git a/tests/btrfs/204.out b/tests/btrfs/204.out
>> new file mode 100644
>> index 00000000..44c7c8ae
>> --- /dev/null
>> +++ b/tests/btrfs/204.out
>> @@ -0,0 +1,5 @@
>> +QA output created by 204
>> +wrote 4096/4096 bytes at offset 0
>> +XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
>> +wrote 8192/8192 bytes at offset 0
>> +XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
>> diff --git a/tests/btrfs/group b/tests/btrfs/group
>> index 6acc6426..7a840177 100644
>> --- a/tests/btrfs/group
>> +++ b/tests/btrfs/group
>> @@ -206,3 +206,4 @@
>> 201 auto quick punch log
>> 202 auto quick subvol snapshot
>> 203 auto quick send clone
>> +204 auto quick log replay
>
> "prealloc" and "punch" groups as well.
>
> Since this just tests another variant of the same problem, maybe it
> could be added to btrfs/172, since that test is very recent and you
> authored it as well.
> Anyway, I don't have a strong preference.
>
> The test itself looks good to me, and with the _require_xfs_io_command
> thing added and the groups (maybe Eryu can add these at commit time):
>
> Reviewed-by: Filipe Manana <fdmanana@suse.com>
>
I like to keep these things discrete, if a test is testing two different things
and it fails I have to go comment out one part and re-run to figure out which
actually failed. Thanks,
Josef
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [PATCH] fstests: add a another gap extent testcase for btrfs
2020-02-20 16:24 ` Filipe Manana
2020-02-20 17:12 ` Josef Bacik
@ 2020-02-23 14:54 ` Eryu Guan
1 sibling, 0 replies; 4+ messages in thread
From: Eryu Guan @ 2020-02-23 14:54 UTC (permalink / raw)
To: Filipe Manana; +Cc: Josef Bacik, linux-btrfs, kernel-team, fstests
On Thu, Feb 20, 2020 at 04:24:37PM +0000, Filipe Manana wrote:
> On Thu, Feb 20, 2020 at 2:39 PM Josef Bacik <josef@toxicpanda.com> wrote:
> >
> > This is a testcase for a corner that I missed when trying to fix gap
> > extents for btrfs. We would end up with gaps if we hole punched past
> > isize and then extended past the gap in a specific way. This is a
> > simple reproducer to show the problem, and has been properly fixed by my
> > patches now.
> >
> > Signed-off-by: Josef Bacik <josef@toxicpanda.com>
> > ---
> > tests/btrfs/204 | 85 +++++++++++++++++++++++++++++++++++++++++++++
> > tests/btrfs/204.out | 5 +++
> > tests/btrfs/group | 1 +
> > 3 files changed, 91 insertions(+)
> > create mode 100755 tests/btrfs/204
> > create mode 100644 tests/btrfs/204.out
> >
> > diff --git a/tests/btrfs/204 b/tests/btrfs/204
> > new file mode 100755
> > index 00000000..0d5c4bed
> > --- /dev/null
> > +++ b/tests/btrfs/204
> > @@ -0,0 +1,85 @@
> > +#! /bin/bash
> > +# SPDX-License-Identifier: GPL-2.0
> > +# Copyright (c) 2020 Facebook. All Rights Reserved.
> > +#
> > +# FS QA Test 204
> > +#
> > +# Validate that without no-holes we do not get a i_size that is after a gap in
> > +# the file extents on disk when punching a hole past i_size. This is fixed by
> > +# the following patches
> > +#
> > +# btrfs: use the file extent tree infrastructure
> > +# btrfs: replace all uses of btrfs_ordered_update_i_size
> > +#
> > +seq=`basename $0`
> > +seqres=$RESULT_DIR/$seq
> > +echo "QA output created by $seq"
> > +
> > +here=`pwd`
> > +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/dmlogwrites
> > +
> > +# remove previous $seqres.full before test
> > +rm -f $seqres.full
> > +
> > +# real QA test starts here
> > +
> > +# Modify as appropriate.
> > +_supported_fs generic
I also changed 'generic' to 'btrfs'
> > +_supported_os Linux
> > +_require_test
> > +_require_scratch
> > +_require_log_writes
>
> _require_xfs_io_command "falloc" "-k"
> _require_xfs_io_command "fpunch"
Added.
>
> > +
> > +_log_writes_init $SCRATCH_DEV
> > +_log_writes_mkfs "-O ^no-holes" >> $seqres.full 2>&1
> > +
> > +# There's not a straightforward way to commit the transaction without also
> > +# flushing dirty pages, so shorten the commit interval to 1 so we're sure to get
> > +# a commit with our broken file
> > +_log_writes_mount -o commit=1
> > +
> > +# This creates a gap extent because fpunch doesn't insert hole extents past
> > +# i_size
> > +xfs_io -f -c "falloc -k 4k 8k" $SCRATCH_MNT/file
> > +xfs_io -f -c "fpunch 4k 4k" $SCRATCH_MNT/file
> > +
> > +# The pwrite extends the i_size to cover the gap extent, and then the truncate
> > +# sets the disk_i_size to 12k because it assumes everything was a-ok.
> > +xfs_io -f -c "pwrite 0 4k" $SCRATCH_MNT/file | _filter_xfs_io
> > +xfs_io -f -c "pwrite 0 8k" $SCRATCH_MNT/file | _filter_xfs_io
> > +xfs_io -f -c "truncate 12k" $SCRATCH_MNT/file
Changed all 'xfs_io' to '$XFS_IO_PROG'.
> > +
> > +# Wait for a transaction commit
> > +sleep 2
> > +
> > +_log_writes_unmount
> > +_log_writes_remove
> > +
> > +cur=$(_log_writes_find_next_fua 0)
> > +echo "cur=$cur" >> $seqres.full
> > +while [ ! -z "$cur" ]; do
> > + _log_writes_replay_log_range $cur $SCRATCH_DEV >> $seqres.full
> > +
> > + # We only care about the fs consistency, so just run fsck, we don't have
> > + # to mount the fs to validate it
> > + _check_scratch_fs
> > +
> > + cur=$(_log_writes_find_next_fua $(($cur + 1)))
> > +done
> > +
> > +# success, all done
> > +status=0
> > +exit
> > diff --git a/tests/btrfs/204.out b/tests/btrfs/204.out
> > new file mode 100644
> > index 00000000..44c7c8ae
> > --- /dev/null
> > +++ b/tests/btrfs/204.out
> > @@ -0,0 +1,5 @@
> > +QA output created by 204
> > +wrote 4096/4096 bytes at offset 0
> > +XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
> > +wrote 8192/8192 bytes at offset 0
> > +XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
> > diff --git a/tests/btrfs/group b/tests/btrfs/group
> > index 6acc6426..7a840177 100644
> > --- a/tests/btrfs/group
> > +++ b/tests/btrfs/group
> > @@ -206,3 +206,4 @@
> > 201 auto quick punch log
> > 202 auto quick subvol snapshot
> > 203 auto quick send clone
> > +204 auto quick log replay
>
> "prealloc" and "punch" groups as well.
Added.
>
> Since this just tests another variant of the same problem, maybe it
> could be added to btrfs/172, since that test is very recent and you
> authored it as well.
> Anyway, I don't have a strong preference.
>
> The test itself looks good to me, and with the _require_xfs_io_command
> thing added and the groups (maybe Eryu can add these at commit time):
>
> Reviewed-by: Filipe Manana <fdmanana@suse.com>
Thanks for the review!
Eryu
>
>
> > --
> > 2.24.1
> >
>
>
> --
> Filipe David Manana,
>
> “Whether you think you can, or you think you can't — you're right.”
^ permalink raw reply [flat|nested] 4+ messages in thread
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2020-02-20 14:38 [PATCH] fstests: add a another gap extent testcase for btrfs Josef Bacik
2020-02-20 16:24 ` Filipe Manana
2020-02-20 17:12 ` Josef Bacik
2020-02-23 14:54 ` Eryu Guan
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