[PATCH V2] xfs_admin: revert online label setting ability

Eric Sandeen
2020-03-02T14:35:12Z

"xfs_admin can't print both label and UUID for mounted filesystems"
https://bugzilla.kernel.org/show_bug.cgi?id=206429

alerted us to the problem that if /any/ options that use xfs_io get
specified to xfs_admin, they are the /only/ ones that get run:

# 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

and thanks to the exit, the xfs_db operations don't get run at all.

We could move on to the xfs_db commands after executing the xfs_io
commands, but we build them all up in parallel at this time:

l) DB_OPTS=$DB_OPTS" -r -c label"
IO_OPTS=$IO_OPTS" -r -c label"
;;

so we'd need to keep track of these, and not re-run them in xfs_db.

Another issue is that prior to this commit, we'd run commands in
command line order.

So I experimented with building up an array of commands, invoking xfs_db
or xfs_io one command at a time as needed for each, and ... it got overly
complicated.

It's broken now, and so far a clean solution isn't evident, and I hate to
leave it broken across another release. So revert it for now.

Reverts: 3f153e051a ("xfs_admin: enable online label getting and setting")

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
---

diff --git a/db/xfs_admin.sh b/db/xfs_admin.sh
index d18959bf..bd325da2 100755
--- a/db/xfs_admin.sh
+++ b/db/xfs_admin.sh
@@ -7,30 +7,8 @@
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 $c in
@@ -38,16 +16,8 @@ do
e) DB_OPTS=$DB_OPTS" -c 'version extflg'";;
f) DB_OPTS=$DB_OPTS" -f";;
j) DB_OPTS=$DB_OPTS" -c 'version log2'";;
- l) DB_OPTS=$DB_OPTS" -r -c label"
- IO_OPTS=$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
- ;;
+ l) DB_OPTS=$DB_OPTS" -r -c label";;
+ L) DB_OPTS=$DB_OPTS" -c 'label "$OPTARG"'";;
p) DB_OPTS=$DB_OPTS" -c 'version projid32bit'";;
u) DB_OPTS=$DB_OPTS" -r -c uuid";;
U) DB_OPTS=$DB_OPTS" -c 'uuid "$OPTARG"'";;
@@ -71,14 +41,6 @@ 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
diff --git a/man/man8/xfs_admin.8 b/man/man8/xfs_admin.8
index 220dd803..8afc873f 100644
--- a/man/man8/xfs_admin.8
+++ b/man/man8/xfs_admin.8
@@ -26,7 +26,7 @@ uses the
.BR xfs_db (8)
command to modify various parameters of a filesystem.
.PP
-Devices that are mounted cannot be modified, except as noted below.
+Devices that are mounted cannot be modified.
Administrators must unmount filesystems before
.BR xfs_admin " or " xfs_db (8)
can convert parameters.
@@ -67,7 +67,6 @@ log buffers).
.TP
.B \-l
Print the current filesystem label.
-This command can be run if the filesystem is mounted.
.TP
.B \-p
Enable 32bit project identifier support (PROJID32BIT feature).
@@ -103,7 +102,6 @@ The filesystem label can be cleared using the special "\c
.B \-\-\c
" value for
.IR label .
-This command can be run if the filesystem is mounted.
.TP
.BI \-U " uuid"
Set the UUID of the filesystem to