Re: [PATCH blktests v1 2/3] nvme/rc: Avoid triggering host nvme-cli autoconnect

[Max Gurtovoy <mgurtovoy@nvidia.com>]

On 20/06/2023 16:27, Daniel Wagner wrote:
> When the host has enabled the udev/systemd autoconnect services for the
> fc transport it interacts with blktests and make tests break.
> 
> nvme-cli learned to ignore connects attemps when using the
> --context command line option paired with a volatile configuration. Thus
> we can mark all the resources created by blktests and avoid any
> interaction with the systemd autoconnect scripts.

why would we like to ignore connect attempts during blktests ?
We define unique nqn/ids/etc. So we never should disturb other running 
services, unless it uses the same parameters, which shouldn't happen.

Agree on setting the hard coded values for hostnqn and hostid instead of 
reading the /etc/nvme/* files. This should do the work IMO, isn't it ?

> 
> Signed-off-by: Daniel Wagner <dwagner@suse.de>
> ---
>   tests/nvme/rc | 73 ++++++++++++++++++++++++++++++++++++++++++++-------
>   1 file changed, 63 insertions(+), 10 deletions(-)
> 
> diff --git a/tests/nvme/rc b/tests/nvme/rc
> index 191f3e2e0c43..00117d314a38 100644
> --- a/tests/nvme/rc
> +++ b/tests/nvme/rc
> @@ -14,8 +14,8 @@ def_remote_wwnn="0x10001100aa000001"
>   def_remote_wwpn="0x20001100aa000001"
>   def_local_wwnn="0x10001100aa000002"
>   def_local_wwpn="0x20001100aa000002"
> -def_hostnqn="$(cat /etc/nvme/hostnqn 2> /dev/null)"
> -def_hostid="$(cat /etc/nvme/hostid 2> /dev/null)"
> +def_hostnqn="nqn.2014-08.org.nvmexpress:uuid:242d4a24-2484-4a80-8234-d0169409c5e8"
> +def_hostid="242d4a24-2484-4a80-8234-d0169409c5e8"
>   nvme_trtype=${nvme_trtype:-"loop"}
>   nvme_img_size=${nvme_img_size:-"1G"}
>   nvme_num_iter=${nvme_num_iter:-"1000"}
> @@ -161,6 +161,50 @@ _nvme_calc_rand_io_size() {
>   	echo "${io_size_kb}k"
>   }
>   
> +_nvme_cli_supports_context() {
> +	if ! nvme connect --help 2>&1 | grep -q context > /dev/null; then
> +		    return 1
> +	fi
> +	return 0
> +}
> +
> +_setup_nvme_cli() {
> +	if ! _nvme_cli_supports_context; then
> +		return
> +	fi
> +
> +	mkdir -p /run/nvme
> +	cat >> /run/nvme/blktests.json <<-EOF
> +	[
> +	  {
> +	    "hostnqn": "${def_hostnqn}",
> +	    "hostid": "${def_hostid}",
> +	    "subsystems": [
> +	      {
> +	        "application": "blktests",
> +	        "nqn": "blktests-subsystem-1",
> +	        "ports": [
> +	          {
> +	            "transport": "fc",
> +	            "traddr": "nn-${def_remote_wwnn}:pn-${def_remote_wwpn}",
> +	            "host_traddr": "nn-${def_local_wwnn}:pn-${def_local_wwpn}"
> +	          }
> +	        ]
> +	      }
> +	    ]
> +	  }
> +	]
> +	EOF
> +}
> +
> +_cleanup_nvme_cli() {
> +	if ! _nvme_cli_supports_context; then
> +		return
> +	fi
> +
> +	rm -f /run/nvme/blktests.json
> +}
> +
>   _nvme_fcloop_add_rport() {
>   	local local_wwnn="$1"
>   	local local_wwpn="$2"
> @@ -235,6 +279,8 @@ _cleanup_fcloop() {
>   	_nvme_fcloop_del_lport "${local_wwnn}" "${local_wwpn}"
>   	_nvme_fcloop_del_rport "${local_wwnn}" "${local_wwpn}" \
>   			       "${remote_wwnn}" "${remote_wwpn}"
> +
> +	_cleanup_nvme_cli
>   }
>   
>   _cleanup_nvmet() {
> @@ -337,6 +383,8 @@ _setup_nvmet() {
>   		def_host_traddr=$(printf "nn-%s:pn-%s" \
>   					 "${def_local_wwnn}" \
>   					 "${def_local_wwpn}")
> +
> +		_setup_nvme_cli
>   	fi
>   }
>   
> @@ -436,18 +484,18 @@ _nvme_connect_subsys() {
>   	trtype="$1"
>   	subsysnqn="$2"
>   
> -	ARGS=(-t "${trtype}" -n "${subsysnqn}")
> +	ARGS=(-t "${trtype}"
> +	      -n "${subsysnqn}"
> +	      --hostnqn="${hostnqn}"
> +	      --hostid="${hostid}")
> +	if _nvme_cli_supports_context; then
> +		ARGS+=(--context="blktests")
> +	fi
>   	if [[ "${trtype}" == "fc" ]] ; then
>   		ARGS+=(-a "${traddr}" -w "${host_traddr}")
>   	elif [[ "${trtype}" != "loop" ]]; then
>   		ARGS+=(-a "${traddr}" -s "${trsvcid}")
>   	fi
> -	if [[ "${hostnqn}" != "$def_hostnqn" ]]; then
> -		ARGS+=(--hostnqn="${hostnqn}")
> -	fi
> -	if [[ "${hostid}" != "$def_hostid" ]]; then
> -		ARGS+=(--hostid="${hostid}")
> -	fi
>   	if [[ -n "${hostkey}" ]]; then
>   		ARGS+=(--dhchap-secret="${hostkey}")
>   	fi
> @@ -482,7 +530,12 @@ _nvme_discover() {
>   	local host_traddr="${3:-$def_host_traddr}"
>   	local trsvcid="${3:-$def_trsvcid}"
>   
> -	ARGS=(-t "${trtype}")
> +	ARGS=(-t "${trtype}"
> +	      --hostnqn="${def_hostnqn}"
> +	      --hostid="${def_hostid}")
> +	if _nvme_cli_supports_context; then
> +		ARGS+=(--context="blktests")
> +	fi
>   	if [[ "${trtype}" = "fc" ]]; then
>   		ARGS+=(-a "${traddr}" -w "${host_traddr}")
>   	elif [[ "${trtype}" != "loop" ]]; then