On 7/2/21 9:58 PM, Darrick J. Wong wrote:
> From: Darrick J. Wong <djwong@xxxxxxxxxx>
>
> Adapt this tool to call xfs_io if the block device in question is
> mounted.
>
> Signed-off-by: Darrick J. Wong <djwong@xxxxxxxxxx>
> ---
> db/xfs_admin.sh | 41 +++++++++++++++++++++++++++++++++++++++--
> 1 file changed, 39 insertions(+), 2 deletions(-)
>
>
> diff --git a/db/xfs_admin.sh b/db/xfs_admin.sh
> index 409975b2..21c9d71b 100755
> --- a/db/xfs_admin.sh
> +++ b/db/xfs_admin.sh
> @@ -8,9 +8,34 @@ status=0
> DB_OPTS=""
> REPAIR_OPTS=""
> REPAIR_DEV_OPTS=""
> +IO_OPTS=""
> LOG_OPTS=""
> USAGE="Usage: xfs_admin [-efjlpuV] [-c 0|1] [-L label] [-O v5_feature] [-r rtdev] [-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.
Not thrilled about the C&P here from spaceman, but I guess by choosing to
use bash long ago, that ship has kinda sailed. (Sourcing another file
would be possible I guess but ... meh, oh well)
> +try_find_loop_dev_for_file() {
> + local x="$(losetup -O NAME -j "$1" 2> /dev/null | tail -n 1)"
> + test -b "$x" && echo "$x"
> +}
> +
> +try_find_mount_point_for_bdev() {
> + local arg="$1"
> +
> + # See if we can map the arg to a loop device
> + loopdev="$(try_find_loop_dev_for_file "${arg}")"
> + test -n "${loopdev}" && arg="${loopdev}"
> +
> + if [ ! -b "${arg}" ]; then
> + return 1
> + fi
> +
> + # 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 "c:efjlL:O:pr:uU:V" c
> do
> case $c in
> @@ -18,8 +43,10 @@ do
> e) DB_OPTS=$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 "$OPTARG"'";
> + IO_OPTS=$IO_OPTS" -c 'label -s "$OPTARG"'";;
> O) REPAIR_OPTS=$REPAIR_OPTS" -c $OPTARG";;
> p) DB_OPTS=$DB_OPTS" -c 'version projid32bit'";;
> r) REPAIR_DEV_OPTS=" -r '$OPTARG'";;
> @@ -43,6 +70,16 @@ case $# in
> LOG_OPTS=" -l '$2'"
> fi
>
> + if [ -n "$IO_OPTS" ]; then
> + mntpt="$(try_find_mount_point_for_bdev "$1")"
> + if [ $? -eq 0 ]; then
> + eval xfs_io -x -p xfs_admin $IO_OPTS "$mntpt"
> + status=$?
> + DB_OPTS=""
> + REPAIR_OPTS=""
> + fi
> + fi
If I read this correctly, specifying either of "-l" or "-L" will now cause
the command to stop executing after the label... but only if it's mounted.
hm yup.
before, when mounted:
# sh db/xfs_admin.sh -lu /dev/pmem0p1
label = ""
UUID = 392591da-ca09-4d4d-8c17-eb8e97ec9f9a
after this patch:
# sh db/xfs_admin.sh -lu /dev/pmem0p1
label = ""
Also, I'm not sure this:
# mount /dev/pmem0p1 /mnt/test
# sh db/xfs_admin.sh -lU generate /dev/pmem0p1
label = ""
#
is really desirable; -U is just silently ignored if it's mounted?
Before the patch, this would have failed with an error.
I wonder if we need to error out on any non-mounted-compliant options, or
simply go ahead and pass non-label db opts to the next stage so it'll
error out as it did before.
Also this is fun behavior that exists today :(
# xfs_admin -l -U generate /dev/pmem0p1
label = "foo"
xfs_admin: not in expert mode, writing disabled
#
('-l' adds -r, overrides the -x and puts it into readonly mode)
> if [ -n "$DB_OPTS" ]
> then
> eval xfs_db -x -p xfs_admin $LOG_OPTS $DB_OPTS "$1"
>
