test/nvme/cuse: Add some helper functions for cuse tests

#!/usr/bin/env bash

#  SPDX-License-Identifier: BSD-3-Clause

#  Copyright (C) 2023 Intel Corporation

#  All rights reserved.

#

testdir=$(readlink -f "$(dirname "${BASH_SOURCE[0]}")")

rootdir=$(readlink -f "$testdir/../../../")

source "$rootdir/test/common/autotest_common.sh"

shopt -s extglob

NVME_CMD="/usr/local/src/nvme-cli/nvme"

rpc_py=$rootdir/scripts/rpc.py

declare -A ctrls=()

declare -A nvmes=()

declare -A bdfs=()

nvme_name=""

nvme_get() {

	local ref=$1 reg val

	shift

	local -gA "$ref=()"

	while IFS=":" read -r reg val; do

		[[ -n $val ]] \

			&& eval "${ref}[${reg//[[:space:]]/}]=\"${val##+([[:space:]])}\""

	done < <($NVME_CMD "$@")

}

scan_nvme_ctrls() {

	# Create set of references and bundle them together in global assoc arrays.

	# Each controller's regs are mapped onto a separate array named as the target

	# ctrl. Each ctrl also gets a dedicated array which holds references to each

	# namespace device. E.g.:

	#

	#  ctrls["nvme0"]=nvme0

	#    nvme0["mn"] nvme0["vid"]

	#  nvmes["nvme0"]=nvme0_ns

	#    nvme0_ns[1]=nvme0n1 nvme0_ns[2]=nvme0n2

	#     nvme0n1["lbaf0"] nvme0n1["ncap"]

	#  bdf["nvme0"]=0000:00:42.0

	#

	# Each of these can be accessed via get*() helpers defined below. E.g.:

	# get_nvme_ctrl_feature nvme0 vid -> 0x8086

	# get_nvme_ns_feature nvme0 1 ncap -> 0x2e9390b0

	# get_nvme_nss nvme0 -> 1 2

	local ctrl ctrl_dev reg val ns pci

	for ctrl in /sys/class/nvme/nvme*; do

		[[ -e $ctrl ]] || continue

		pci=$(< "$ctrl/address")

		pci_can_use "$pci" || continue

		ctrl_dev=${ctrl##*/}

		nvme_get "$ctrl_dev" id-ctrl "/dev/$ctrl_dev"

		local -n _ctrl_ns=${ctrl_dev}_ns

		for ns in "$ctrl/${ctrl##*/}n"*; do

			[[ -e $ns ]] || continue

			ns_dev=${ns##*/}

			nvme_get "$ns_dev" id-ns "/dev/$ns_dev"

			_ctrl_ns[${ns##*n}]=$ns_dev

		done

		ctrls["$ctrl_dev"]=$ctrl_dev

		nvmes["$ctrl_dev"]=${ctrl_dev}_ns

		bdfs["$ctrl_dev"]=$pci

	done

}

get_nvme_ctrl_feature() {

	local ctrl=$1 reg=${2:-cntlid}

	[[ -n ${ctrls["$ctrl"]} ]] || return 1

	local -n _ctrl=${ctrls["$ctrl"]}

	[[ -n ${_ctrl["$reg"]} ]] || return 1

	echo "${_ctrl["$reg"]}"

}

get_nvme_ns_feature() {

	local ctrl=$1 ns=$2 reg=${3:-nsze}

	[[ -n ${nvmes["$ctrl"]} ]] || return 1

	local -n _nss=${nvmes["$ctrl"]}

	[[ -n ${_nss[ns]} ]] || return 1

	local -n _ns=${_nss[ns]}

	[[ -n ${_ns["$reg"]} ]] || return 1

	echo "${_ns["$reg"]}"

}

get_nvme_nss() {

	local ctrl=$1

	[[ -n ${nvmes["$ctrl"]} ]] || return 1

	local -n _nss=${nvmes["$ctrl"]}

	echo "${!_nss[@]}"

}

get_active_lbaf() {

	local ctrl=$1 ns=$2 reg lbaf

	[[ -n ${nvmes["$ctrl"]} ]] || return 1

	local -n _nss=${nvmes["$ctrl"]}

	[[ -n ${_nss[ns]} ]] || return 1

	local -n _ns=${_nss[ns]}

	for reg in "${!_ns[@]}"; do

		[[ $reg == lbaf* ]] || continue

		[[ ${_ns["$reg"]} == *"in use"* ]] || continue

		echo "${reg/lbaf/}" && return 0

	done

	return 1

}