Re: [PATCH blktests 1/2] zbd/rc: Support dm-crypt

[Bart Van Assche <bvanassche@acm.org>]

On 7/13/21 3:12 AM, Shin'ichiro Kawasaki wrote:
> -	# Parse dm table lines for dm-linear or dm-flakey target
> +	if _test_dev_has_dm_map crypt; then
> +		dev_idx=6
> +		off_idx=7
> +	fi
> +
> +	# Parse dm table lines for dm-linear, dm-flakey or dm-crypt target
>  	while read -r -a tbl_line; do
>  		local -i map_start=${tbl_line[0]}
>  		local -i map_end=$((tbl_line[0] + tbl_line[1]))
> @@ -355,10 +362,11 @@ _get_dev_container_and_sector() {
>  			continue
>  		fi
>  
> -		offset=${tbl_line[4]}
> -		if ! cont_dev=$(_get_dev_path_by_id "${tbl_line[3]}"); then
> +		offset=${tbl_line[off_idx]}
> +		if ! cont_dev=$(_get_dev_path_by_id \
> +					"${tbl_line[dev_idx]}"); then
>  			echo -n "Cannot access to container device: "
> -			echo "${tbl_line[3]}"
> +			echo "${tbl_line[dev_idx]}"
>  			return 1
>  		fi

To me the above code looks like code that is hard to maintain. Can the
above parser be replaced by reading /sys/block/*/slaves? An example from
my workstation for dm-crypt:

$ ls /sys/block/dm-0/slaves
nvme0n1p2

Thanks,

Bart.