On Mon, Nov 14, 2022 at 08:35:02AM +0000, Xiao Yang wrote:
> It is unnecssary to always create a dm-log-writes device
> based on the entire size of the target/underlying device.
>
> Signed-off-by: Xiao Yang <yangx.jy@xxxxxxxxxxx>
Reviewed-by: Darrick J. Wong <djwong@xxxxxxxxxx>
--D
> ---
> common/dmlogwrites | 18 ++++++++++++++++--
> 1 file changed, 16 insertions(+), 2 deletions(-)
>
> diff --git a/common/dmlogwrites b/common/dmlogwrites
> index 9fa1c977..c1c85de9 100644
> --- a/common/dmlogwrites
> +++ b/common/dmlogwrites
> @@ -59,14 +59,28 @@ _require_log_writes_dax_mountopt()
> fi
> }
>
> +# Set up a dm-log-writes device
> +#
> +# blkdev: the specified target device
> +# length(optional): the mapped length in bytes
> +# Note that the entire size of the target device will be used
> +# if length is not specified.
> _log_writes_init()
> {
> - blkdev=$1
> + local blkdev=$1
> + local length=$2
> + local BLK_DEV_SIZE
>
> [ -z "$blkdev" ] && _fail \
> "block dev must be specified for _log_writes_init"
>
> - local BLK_DEV_SIZE=`blockdev --getsz $blkdev`
> + if [ -z "$length" ]; then
> + BLK_DEV_SIZE=`blockdev --getsz $blkdev`
> + else
> + local blksz=`blockdev --getss $blkdev`
> + BLK_DEV_SIZE=$((length / blksz))
> + fi
> +
> LOGWRITES_NAME=logwrites-test
> LOGWRITES_DMDEV=/dev/mapper/$LOGWRITES_NAME
> LOGWRITES_TABLE="0 $BLK_DEV_SIZE log-writes $blkdev $LOGWRITES_DEV"
> --
> 2.34.1
>
