Re: [PATCH 3/4] common/populate: move decompression code to _{xfs,ext4}_mdrestore

["Darrick J. Wong" <djwong@kernel.org>]

On Sat, Dec 17, 2022 at 02:50:15PM +0800, Zorro Lang wrote:
> On Tue, Dec 13, 2022 at 11:45:28AM -0800, Darrick J. Wong wrote:
> > From: Darrick J. Wong <djwong@kernel.org>
> > 
> > Move the metadump decompression code to the per-filesystem mdrestore
> > commands so that everyone can take advantage of them.  This enables the
> > XFS and ext4 _mdrestore helpers to handle metadata dumps compressed with
> > their respective _metadump helpers.
> > 
> > In turn, this means that the xfs fuzz tests can now handle the
> > compressed metadumps created by the _scratch_populate_cached helper.
> > This is key to unbreaking fuzz testing for xfs.
> > 
> > Signed-off-by: Darrick J. Wong <djwong@kernel.org>
> > ---
> >  common/ext4     |   13 ++++++++++++-
> >  common/fuzzy    |    2 +-
> >  common/populate |   15 ++-------------
> >  common/xfs      |   15 +++++++++++++--
> >  4 files changed, 28 insertions(+), 17 deletions(-)
> > 
> > 
> > diff --git a/common/ext4 b/common/ext4
> > index dc2e4e59cc..cadf1a7974 100644
> > --- a/common/ext4
> > +++ b/common/ext4
> > @@ -129,9 +129,20 @@ _ext4_mdrestore()
> >  {
> >  	local metadump="$1"
> >  	local device="$2"
> > -	shift; shift
> > +	local compressopt="$3"
> 
> I didn't see this variable is used in this function, do I missed something?

Oops.  I missed that this variable isn't necessary at all. :(

--D

> > +	shift; shift; shift
> >  	local options="$@"
> >  
> > +	# If we're configured for compressed dumps and there isn't already an
> > +	# uncompressed dump, see if we can use DUMP_COMPRESSOR to decompress
> > +	# something.
> > +	if [ ! -e "$metadump" ] && [ -n "$DUMP_COMPRESSOR" ]; then
> > +		for compr in "$metadump".*; do
> > +			[ -e "$compr" ] && $DUMP_COMPRESSOR -d -f -k "$compr" && break
> > +		done
> > +	fi
> > +	test -r "$metadump" || return 1
> > +
> >  	$E2IMAGE_PROG $options -r "${metadump}" "${SCRATCH_DEV}"
> >  }
> >  
> > diff --git a/common/fuzzy b/common/fuzzy
> > index fad79124e5..e634815eec 100644
> > --- a/common/fuzzy
> > +++ b/common/fuzzy
> > @@ -159,7 +159,7 @@ __scratch_xfs_fuzz_mdrestore()
> >  	test -e "${POPULATE_METADUMP}" || _fail "Need to set POPULATE_METADUMP"
> >  
> >  	__scratch_xfs_fuzz_unmount
> > -	_xfs_mdrestore "${POPULATE_METADUMP}" "${SCRATCH_DEV}"
> > +	_xfs_mdrestore "${POPULATE_METADUMP}" "${SCRATCH_DEV}" compress
> >  }
> >  
> >  __fuzz_notify() {
> > diff --git a/common/populate b/common/populate
> > index f382c40aca..96866ee4cf 100644
> > --- a/common/populate
> > +++ b/common/populate
> > @@ -848,20 +848,9 @@ _scratch_populate_cache_tag() {
> >  _scratch_populate_restore_cached() {
> >  	local metadump="$1"
> >  
> > -	# If we're configured for compressed dumps and there isn't already an
> > -	# uncompressed dump, see if we can use DUMP_COMPRESSOR to decompress
> > -	# something.
> > -	if [ -n "$DUMP_COMPRESSOR" ]; then
> > -		for compr in "$metadump".*; do
> > -			[ -e "$compr" ] && $DUMP_COMPRESSOR -d -f -k "$compr" && break
> > -		done
> > -	fi
> > -
> > -	test -r "$metadump" || return 1
> > -
> >  	case "${FSTYP}" in
> >  	"xfs")
> > -		_xfs_mdrestore "${metadump}" "${SCRATCH_DEV}"
> > +		_xfs_mdrestore "${metadump}" "${SCRATCH_DEV}" compress
> >  		res=$?
> >  		test $res -ne 0 && return $res
> >  
> > @@ -876,7 +865,7 @@ _scratch_populate_restore_cached() {
> >  		return $res
> >  		;;
> >  	"ext2"|"ext3"|"ext4")
> > -		_ext4_mdrestore "${metadump}" "${SCRATCH_DEV}"
> > +		_ext4_mdrestore "${metadump}" "${SCRATCH_DEV}" compress
> >  		ret=$?
> >  		test $ret -ne 0 && return $ret
> >  
> > diff --git a/common/xfs b/common/xfs
> > index 216dab3bcd..833c2f4368 100644
> > --- a/common/xfs
> > +++ b/common/xfs
> > @@ -641,9 +641,20 @@ _xfs_metadump() {
> >  _xfs_mdrestore() {
> >  	local metadump="$1"
> >  	local device="$2"
> > -	shift; shift
> > +	local compressopt="$3"
> 
> I didn't see this variable is used in this function either.
> 
> > +	shift; shift; shift
> >  	local options="$@"
> >  
> > +	# If we're configured for compressed dumps and there isn't already an
> > +	# uncompressed dump, see if we can use DUMP_COMPRESSOR to decompress
> > +	# something.
> > +	if [ ! -e "$metadump" ] && [ -n "$DUMP_COMPRESSOR" ]; then
> > +		for compr in "$metadump".*; do
> > +			[ -e "$compr" ] && $DUMP_COMPRESSOR -d -f -k "$compr" && break
> > +		done
> > +	fi
> > +	test -r "$metadump" || return 1
> > +
> >  	$XFS_MDRESTORE_PROG $options "${metadump}" "${device}"
> >  }
> >  
> > @@ -666,7 +677,7 @@ _scratch_xfs_mdrestore()
> >  	local metadump=$1
> >  	shift
> >  
> > -	_xfs_mdrestore "$metadump" "$SCRATCH_DEV" "$@"
> > +	_xfs_mdrestore "$metadump" "$SCRATCH_DEV" nocompress "$@"
> >  }
> >  
> >  # run xfs_check and friends on a FS.
> > 
>