[PATCH 0/2] xfs_admin: unify online/offline fs label setting

[PATCH 0/2] xfs_admin: unify online/offline fs label setting

[Darrick J. Wong]

Hi all,

Here are two fixes for the xfs_admin script.  The first enables callers
to pass an external log device, because xfs_db requires that to work on
filesystems that do not have an internal log.

The second patch enables xfs_admin to call xfs_io, which is then used to
pass label get and set commands (-l and -L) to the kernel (via xfs_io) if
the filesystem is mounted.

This is an extraordinary way to destroy everything.  Enjoy!
Comments and questions are, as always, welcome.

--D

[PATCH 1/2] xfs_admin: support external log devices

[Darrick J. Wong]

From: Darrick J. Wong <darrick.wong@oracle.com>

Add to xfs_admin the ability to pass external log devices to xfs_db.
This is necessary to make changes on such filesystems.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
---
 db/xfs_admin.sh      |   12 ++++++++++--
 man/man8/xfs_admin.8 |    3 +++
 2 files changed, 13 insertions(+), 2 deletions(-)


diff --git a/db/xfs_admin.sh b/db/xfs_admin.sh
index 305ef2b7..bd325da2 100755
--- a/db/xfs_admin.sh
+++ b/db/xfs_admin.sh
@@ -7,7 +7,7 @@
 status=0
 DB_OPTS=""
 REPAIR_OPTS=""
-USAGE="Usage: xfs_admin [-efjlpuV] [-c 0|1] [-L label] [-U uuid] device"
+USAGE="Usage: xfs_admin [-efjlpuV] [-c 0|1] [-L label] [-U uuid] device [logdev]"
 
 while getopts "efjlpuc:L:U:V" c
 do
@@ -33,7 +33,15 @@ done
 set -- extra $@
 shift $OPTIND
 case $# in
-	1)	if [ -n "$DB_OPTS" ]
+	1|2)
+		# Pick up the log device, if present
+		if [ -n "$2" ]; then
+			DB_OPTS=$DB_OPTS" -l '$2'"
+			test -n "$REPAIR_OPTS" && \
+				REPAIR_OPTS=$REPAIR_OPTS" -l '$2'"
+		fi
+
+		if [ -n "$DB_OPTS" ]
 		then
 			eval xfs_db -x -p xfs_admin $DB_OPTS $1
 			status=$?
diff --git a/man/man8/xfs_admin.8 b/man/man8/xfs_admin.8
index 20a114f5..d7942418 100644
--- a/man/man8/xfs_admin.8
+++ b/man/man8/xfs_admin.8
@@ -15,6 +15,9 @@ xfs_admin \- change parameters of an XFS filesystem
 .I uuid
 ]
 .I device
+[
+.I logdev
+]
 .br
 .B xfs_admin \-V
 .SH DESCRIPTION

[PATCH 2/2] xfs_admin: enable online label getting and setting

[Darrick J. Wong]

From: Darrick J. Wong <darrick.wong@oracle.com>

Connect xfs_admin -L to the xfs_io label command so that we can get and
set the label for a live filesystem.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
---
 db/xfs_admin.sh |   42 ++++++++++++++++++++++++++++++++++++++++--
 1 file changed, 40 insertions(+), 2 deletions(-)


diff --git a/db/xfs_admin.sh b/db/xfs_admin.sh
index bd325da2..d18959bf 100755
--- a/db/xfs_admin.sh
+++ b/db/xfs_admin.sh
@@ -7,8 +7,30 @@
 status=0
 DB_OPTS=""
 REPAIR_OPTS=""
+IO_OPTS=""
 USAGE="Usage: xfs_admin [-efjlpuV] [-c 0|1] [-L label] [-U uuid] device [logdev]"
 
+# Try to find a loop device associated with a file.  We only want to return
+# one loopdev (multiple loop devices can attach to a single file) so we grab
+# the last line and return it if it's actually a block device.
+try_find_loop_dev_for_file() {
+	local x="$(losetup -O NAME -j "$1" 2> /dev/null | tail -n 1)"
+	test -b "$x" && echo "$x"
+}
+
+# See if we can find a mount point for the argument.
+find_mntpt_for_arg() {
+	local arg="$1"
+
+	# See if we can map the arg to a loop device
+	local loopdev="$(try_find_loop_dev_for_file "${arg}")"
+	test -n "$loopdev" && arg="$loopdev"
+
+	# If we find a mountpoint for the device, do a live query;
+	# otherwise try reading the fs with xfs_db.
+	findmnt -t xfs -f -n -o TARGET "${arg}" 2> /dev/null
+}
+
 while getopts "efjlpuc:L:U:V" c
 do
 	case $c in
@@ -16,8 +38,16 @@ do
 	e)	DB_OPTS=$DB_OPTS" -c 'version extflg'";;
 	f)	DB_OPTS=$DB_OPTS" -f";;
 	j)	DB_OPTS=$DB_OPTS" -c 'version log2'";;
-	l)	DB_OPTS=$DB_OPTS" -r -c label";;
-	L)	DB_OPTS=$DB_OPTS" -c 'label "$OPTARG"'";;
+	l)	DB_OPTS=$DB_OPTS" -r -c label"
+		IO_OPTS=$IO_OPTS" -r -c label"
+		;;
+	L)	DB_OPTS=$DB_OPTS" -c 'label "$OPTARG"'"
+		if [ "$OPTARG" = "--" ]; then
+			IO_OPTS=$IO_OPTS" -c 'label -c'"
+		else
+			IO_OPTS=$IO_OPTS" -c 'label -s "$OPTARG"'"
+		fi
+		;;
 	p)	DB_OPTS=$DB_OPTS" -c 'version projid32bit'";;
 	u)	DB_OPTS=$DB_OPTS" -r -c uuid";;
 	U)	DB_OPTS=$DB_OPTS" -c 'uuid "$OPTARG"'";;
@@ -41,6 +71,14 @@ case $# in
 				REPAIR_OPTS=$REPAIR_OPTS" -l '$2'"
 		fi
 
+		# Try making the changes online, if supported
+		if [ -n "$IO_OPTS" ] && mntpt="$(find_mntpt_for_arg "$1")"
+		then
+			eval xfs_io -x -p xfs_admin $IO_OPTS "$mntpt"
+			test "$?" -eq 0 && exit 0
+		fi
+
+		# Otherwise try offline changing
 		if [ -n "$DB_OPTS" ]
 		then
 			eval xfs_db -x -p xfs_admin $DB_OPTS $1

Re: [PATCH 1/2] xfs_admin: support external log devices

[Eric Sandeen]

On 12/2/19 11:37 AM, Darrick J. Wong wrote:
> From: Darrick J. Wong <darrick.wong@oracle.com>
> 
> Add to xfs_admin the ability to pass external log devices to xfs_db.
> This is necessary to make changes on such filesystems.
> 
> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
> ---
>  db/xfs_admin.sh      |   12 ++++++++++--
>  man/man8/xfs_admin.8 |    3 +++
>  2 files changed, 13 insertions(+), 2 deletions(-)
> 
> 
> diff --git a/db/xfs_admin.sh b/db/xfs_admin.sh
> index 305ef2b7..bd325da2 100755
> --- a/db/xfs_admin.sh
> +++ b/db/xfs_admin.sh
> @@ -7,7 +7,7 @@
>  status=0
>  DB_OPTS=""
>  REPAIR_OPTS=""
> -USAGE="Usage: xfs_admin [-efjlpuV] [-c 0|1] [-L label] [-U uuid] device"
> +USAGE="Usage: xfs_admin [-efjlpuV] [-c 0|1] [-L label] [-U uuid] device [logdev]"
>  
>  while getopts "efjlpuc:L:U:V" c
>  do
> @@ -33,7 +33,15 @@ done
>  set -- extra $@
>  shift $OPTIND
>  case $# in
> -	1)	if [ -n "$DB_OPTS" ]
> +	1|2)
> +		# Pick up the log device, if present
> +		if [ -n "$2" ]; then
> +			DB_OPTS=$DB_OPTS" -l '$2'"
> +			test -n "$REPAIR_OPTS" && \
> +				REPAIR_OPTS=$REPAIR_OPTS" -l '$2'"
> +		fi
> +
> +		if [ -n "$DB_OPTS" ]
>  		then
>  			eval xfs_db -x -p xfs_admin $DB_OPTS $1
>  			status=$?
> diff --git a/man/man8/xfs_admin.8 b/man/man8/xfs_admin.8
> index 20a114f5..d7942418 100644
> --- a/man/man8/xfs_admin.8
> +++ b/man/man8/xfs_admin.8
> @@ -15,6 +15,9 @@ xfs_admin \- change parameters of an XFS filesystem
>  .I uuid
>  ]
>  .I device
> +[
> +.I logdev
> +]

logdev should be marked as optional, right?  [logdev] ?
And documented as to when this arg should (or should not be) used?

-Eric

Re: [PATCH 1/2] xfs_admin: support external log devices

[Darrick J. Wong]

On Mon, Dec 02, 2019 at 11:41:13AM -0600, Eric Sandeen wrote:
> 
> 
> On 12/2/19 11:37 AM, Darrick J. Wong wrote:
> > From: Darrick J. Wong <darrick.wong@oracle.com>
> > 
> > Add to xfs_admin the ability to pass external log devices to xfs_db.
> > This is necessary to make changes on such filesystems.
> > 
> > Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
> > ---
> >  db/xfs_admin.sh      |   12 ++++++++++--
> >  man/man8/xfs_admin.8 |    3 +++
> >  2 files changed, 13 insertions(+), 2 deletions(-)
> > 
> > 
> > diff --git a/db/xfs_admin.sh b/db/xfs_admin.sh
> > index 305ef2b7..bd325da2 100755
> > --- a/db/xfs_admin.sh
> > +++ b/db/xfs_admin.sh
> > @@ -7,7 +7,7 @@
> >  status=0
> >  DB_OPTS=""
> >  REPAIR_OPTS=""
> > -USAGE="Usage: xfs_admin [-efjlpuV] [-c 0|1] [-L label] [-U uuid] device"
> > +USAGE="Usage: xfs_admin [-efjlpuV] [-c 0|1] [-L label] [-U uuid] device [logdev]"
> >  
> >  while getopts "efjlpuc:L:U:V" c
> >  do
> > @@ -33,7 +33,15 @@ done
> >  set -- extra $@
> >  shift $OPTIND
> >  case $# in
> > -	1)	if [ -n "$DB_OPTS" ]
> > +	1|2)
> > +		# Pick up the log device, if present
> > +		if [ -n "$2" ]; then
> > +			DB_OPTS=$DB_OPTS" -l '$2'"
> > +			test -n "$REPAIR_OPTS" && \
> > +				REPAIR_OPTS=$REPAIR_OPTS" -l '$2'"
> > +		fi
> > +
> > +		if [ -n "$DB_OPTS" ]
> >  		then
> >  			eval xfs_db -x -p xfs_admin $DB_OPTS $1
> >  			status=$?
> > diff --git a/man/man8/xfs_admin.8 b/man/man8/xfs_admin.8
> > index 20a114f5..d7942418 100644
> > --- a/man/man8/xfs_admin.8
> > +++ b/man/man8/xfs_admin.8
> > @@ -15,6 +15,9 @@ xfs_admin \- change parameters of an XFS filesystem
> >  .I uuid
> >  ]
> >  .I device
> > +[
> > +.I logdev
> > +]
> 
> logdev should be marked as optional, right?  [logdev] ?

It is.

> And documented as to when this arg should (or should not be) used?

Yes.  Will fix that.

--D

> -Eric

[PATCH 0/2] xfs_admin: unify online/offline fs label setting

[Darrick J. Wong]

Hi all,

Unify the online and offline label setting code paths in xfs_admin so
that one program can handle both.

If you're going to start using this mess, you probably ought to just
pull from my git trees, which are linked below.

This is an extraordinary way to destroy everything.  Enjoy!
Comments and questions are, as always, welcome.

--D

fstests git tree:
https://git.kernel.org/cgit/linux/kernel/git/djwong/xfstests-dev.git/log/?h=online-label-setting

[PATCH 0/2] xfs_admin: unify online/offline fs label setting

[Darrick J. Wong]

Hi all,

Unify the online and offline label setting code paths in xfs_admin so
that one program can handle both.

If you're going to start using this mess, you probably ought to just
pull from my git trees, which are linked below.

This is an extraordinary way to destroy everything.  Enjoy!
Comments and questions are, as always, welcome.

--D

fstests git tree:
https://git.kernel.org/cgit/linux/kernel/git/djwong/xfstests-dev.git/log/?h=online-label-setting