[PATCH v3] btrfs-progs: misc-tests: Superblock corruption and recovery using backup.

[PATCH v3] btrfs-progs: misc-tests: Superblock corruption and recovery using backup.

[Lakshmipathi.G]

Test script to recover damaged primary superblock using backup superblock.

Signed-off-by: Lakshmipathi.G <Lakshmipathi.G@giis.co.in>
---
 .../019-fix-superblock-corruption/test.sh          | 36 ++++++++++++++++++++++
 1 file changed, 36 insertions(+)
 create mode 100755 tests/misc-tests/019-fix-superblock-corruption/test.sh

diff --git a/tests/misc-tests/019-fix-superblock-corruption/test.sh b/tests/misc-tests/019-fix-superblock-corruption/test.sh
new file mode 100755
index 0000000..95815e4
--- /dev/null
+++ b/tests/misc-tests/019-fix-superblock-corruption/test.sh
@@ -0,0 +1,36 @@
+#!/bin/bash
+#
+# Corrupt primary superblock and restore it using backup superblock.
+#
+
+source $TOP/tests/common
+
+check_prereq btrfs-select-super
+check_prereq btrfs
+
+setup_root_helper
+prepare_test_dev 512M
+
+FIRST_SUPERBLOCK_OFFSET=65536
+
+test_superblock_restore()
+{
+	run_check $SUDO_HELPER $TOP/mkfs.btrfs -f $TEST_DEV
+
+	# Corrupt superblock checksum
+        dd if=/dev/zero of=$TEST_DEV seek=$FIRST_SUPERBLOCK_OFFSET bs=1 \
+        count=4  conv=notrunc &> /dev/null
+	# Run btrfs check to detect corruption
+	$TOP/btrfs check $TEST_DEV >& /dev/null && \
+		_fail "btrfs check should detect corruption"
+	# Copy backup superblock to primary
+	run_check $TOP/btrfs-select-super -s 1 $TEST_DEV
+
+	echo "Performing btrfs check" &>> $RESULTS
+	$TOP/btrfs check $TEST_DEV &>> $RESULTS
+        if [ $? -ne 0 ]; then
+		_fail "Failed to fix superblock."
+        fi
+}
+
+test_superblock_restore
-- 
2.7.4

Re: [PATCH v3] btrfs-progs: misc-tests: Superblock corruption and recovery using backup.

[David Sterba]

On Fri, Feb 17, 2017 at 04:01:59AM +0530, Lakshmipathi.G wrote:
> Test script to recover damaged primary superblock using backup superblock.
> 
> Signed-off-by: Lakshmipathi.G <Lakshmipathi.G@giis.co.in>

Thanks for the test, a few comments below.

> ---
>  .../019-fix-superblock-corruption/test.sh          | 36 ++++++++++++++++++++++
>  1 file changed, 36 insertions(+)
>  create mode 100755 tests/misc-tests/019-fix-superblock-corruption/test.sh
> 
> diff --git a/tests/misc-tests/019-fix-superblock-corruption/test.sh b/tests/misc-tests/019-fix-superblock-corruption/test.sh
> new file mode 100755
> index 0000000..95815e4
> --- /dev/null
> +++ b/tests/misc-tests/019-fix-superblock-corruption/test.sh
> @@ -0,0 +1,36 @@
> +#!/bin/bash
> +#
> +# Corrupt primary superblock and restore it using backup superblock.
> +#
> +
> +source $TOP/tests/common
> +
> +check_prereq btrfs-select-super
> +check_prereq btrfs
> +
> +setup_root_helper
> +prepare_test_dev 512M
> +
> +FIRST_SUPERBLOCK_OFFSET=65536
> +
> +test_superblock_restore()
> +{
> +	run_check $SUDO_HELPER $TOP/mkfs.btrfs -f $TEST_DEV
> +
> +	# Corrupt superblock checksum
> +        dd if=/dev/zero of=$TEST_DEV seek=$FIRST_SUPERBLOCK_OFFSET bs=1 \
> +        count=4  conv=notrunc &> /dev/null
> +	# Run btrfs check to detect corruption
> +	$TOP/btrfs check $TEST_DEV >& /dev/null && \
> +		_fail "btrfs check should detect corruption"

No run_check? In general all test output is desired and should be in the
test log so you can use 'run_mayfail'. Also, please keep the entier
output and don't redirect it to /dev/null .

> +	# Copy backup superblock to primary
> +	run_check $TOP/btrfs-select-super -s 1 $TEST_DEV
> +
> +	echo "Performing btrfs check" &>> $RESULTS

Use _log for that

> +	$TOP/btrfs check $TEST_DEV &>> $RESULTS

Use run_check

> +        if [ $? -ne 0 ]; then
> +		_fail "Failed to fix superblock."

And this would be unnecessary.

I've added a section to tests/README.md to describe the common coding
practices. Feel free to read/update/fix. Older tests could violate the
recommendations so at least new tests are in line and we'll update the
rest incrementally.

Re: [PATCH v3] btrfs-progs: misc-tests: Superblock corruption and recovery using backup.

[Lakshmipathi.G]

On Mon, Mar 13, 2017 at 06:15:04PM +0100, David Sterba wrote:
> On Fri, Feb 17, 2017 at 04:01:59AM +0530, Lakshmipathi.G wrote:
> > Test script to recover damaged primary superblock using backup superblock.
> > 
> > Signed-off-by: Lakshmipathi.G <Lakshmipathi.G@giis.co.in>
> 
> Thanks for the test, a few comments below.
> 
> > ---
> >  .../019-fix-superblock-corruption/test.sh          | 36 ++++++++++++++++++++++
> >  1 file changed, 36 insertions(+)
> >  create mode 100755 tests/misc-tests/019-fix-superblock-corruption/test.sh
> > 
> > diff --git a/tests/misc-tests/019-fix-superblock-corruption/test.sh b/tests/misc-tests/019-fix-superblock-corruption/test.sh
> > new file mode 100755
> > index 0000000..95815e4
> > --- /dev/null
> > +++ b/tests/misc-tests/019-fix-superblock-corruption/test.sh
> > @@ -0,0 +1,36 @@
> > +#!/bin/bash
> > +#
> > +# Corrupt primary superblock and restore it using backup superblock.
> > +#
> > +
> > +source $TOP/tests/common
> > +
> > +check_prereq btrfs-select-super
> > +check_prereq btrfs
> > +
> > +setup_root_helper
> > +prepare_test_dev 512M
> > +
> > +FIRST_SUPERBLOCK_OFFSET=65536
> > +
> > +test_superblock_restore()
> > +{
> > +	run_check $SUDO_HELPER $TOP/mkfs.btrfs -f $TEST_DEV
> > +
> > +	# Corrupt superblock checksum
> > +        dd if=/dev/zero of=$TEST_DEV seek=$FIRST_SUPERBLOCK_OFFSET bs=1 \
> > +        count=4  conv=notrunc &> /dev/null
> > +	# Run btrfs check to detect corruption
> > +	$TOP/btrfs check $TEST_DEV >& /dev/null && \
> > +		_fail "btrfs check should detect corruption"
> 
> No run_check? In general all test output is desired and should be in the
> test log so you can use 'run_mayfail'. Also, please keep the entier
> output and don't redirect it to /dev/null .
> 
> > +	# Copy backup superblock to primary
> > +	run_check $TOP/btrfs-select-super -s 1 $TEST_DEV
> > +
> > +	echo "Performing btrfs check" &>> $RESULTS
> 
> Use _log for that
> 
> > +	$TOP/btrfs check $TEST_DEV &>> $RESULTS
> 
> Use run_check
> 
> > +        if [ $? -ne 0 ]; then
> > +		_fail "Failed to fix superblock."
> 
> And this would be unnecessary.
> 
> I've added a section to tests/README.md to describe the common coding
> practices. Feel free to read/update/fix. Older tests could violate the
> recommendations so at least new tests are in line and we'll update the
> rest incrementally.

Just sent a new patch(v4), addressing above review comments.thanks.

Cheers.
Lakshmipathi.G