#
# This file and its contents are supplied under the terms of the
# Common Development and Distribution License ("CDDL"), version 1.0.
# You may only use this file in accordance with the terms of version
# 1.0 of the CDDL.
#
# A full copy of the text of the CDDL should have accompanied this
# source.  A copy of the CDDL is also available via the Internet at
# http://www.illumos.org/license/CDDL.
#

#
# Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
# Use is subject to license terms.
# Copyright (c) 2012, 2016 by Delphix. All rights reserved.
# Copyright 2016 Nexenta Systems, Inc.
# Copyright (c) 2016, 2017 by Intel Corporation. All rights reserved.
# Copyright (c) 2017 Lawrence Livermore National Security, LLC.
# Copyright (c) 2017 Datto Inc.
# Copyright (c) 2017 Open-E, Inc. All Rights Reserved.
#

#
# Returns SCSI host number for the given disk
#
function get_scsi_host #disk
{
	typeset disk=$1
	ls /sys/block/${disk}/device/scsi_device | cut -d : -f 1
}

#
# Cause a scan of all scsi host adapters by default
#
# $1 optional host number
#
function scan_scsi_hosts
{
	typeset hostnum=${1}

	if is_linux; then
		if [[ -z $hostnum ]]; then
			for host in /sys/class/scsi_host/host*; do
				log_must eval "echo '- - -' > $host/scan"
			done
		else
			log_must eval \
			    "echo /sys/class/scsi_host/host$hostnum/scan" \
			    > /dev/null
			log_must eval \
			    "echo '- - -' > /sys/class/scsi_host/host$hostnum/scan"
		fi
	fi
}

#
# Wait for newly created block devices to have their minors created.
#
function block_device_wait
{
	if is_linux; then
		udevadm trigger
		udevadm settle
	fi
}

#
# Check if the given device is physical device
#
function is_physical_device #device
{
	typeset device=${1#$DEV_DSKDIR}
	device=${device#$DEV_RDSKDIR}

	if is_linux; then
		[[ -b "$DEV_DSKDIR/$device" ]] && \
		[[ -f /sys/module/loop/parameters/max_part ]]
		return $?
	else
		echo $device | egrep "^c[0-F]+([td][0-F]+)+$" > /dev/null 2>&1
		return $?
	fi
}

#
# Check if the given device is a real device (ie SCSI device)
#
function is_real_device #disk
{
	typeset disk=$1
	[[ -z $disk ]] && log_fail "No argument for disk given."

	if is_linux; then
		lsblk $DEV_RDSKDIR/$disk -o TYPE 2>/dev/null | \
		    egrep disk >/dev/null
		return $?
	fi
}

#
# Check if the given device is a loop device
#
function is_loop_device #disk
{
	typeset disk=$1
	[[ -z $disk ]] && log_fail "No argument for disk given."

	if is_linux; then
		lsblk $DEV_RDSKDIR/$disk -o TYPE 2>/dev/null | \
		    egrep loop >/dev/null
		return $?
	fi
}

#
# Check if the given device is a multipath device and if there is a sybolic
# link to a device mapper and to a disk
# Currently no support for dm devices alone without multipath
#
function is_mpath_device #disk
{
	typeset disk=$1
	[[ -z $disk ]] && log_fail "No argument for disk given."

	if is_linux; then
		lsblk $DEV_MPATHDIR/$disk -o TYPE 2>/dev/null | \
		   egrep mpath >/dev/null
		if (($? == 0)); then
			readlink $DEV_MPATHDIR/$disk > /dev/null 2>&1
			return $?
		else
			return $?
		fi
	fi
}

# Set the slice prefix for disk partitioning depending
# on whether the device is a real, multipath, or loop device.
# Currently all disks have to be of the same type, so only
# checks first disk to determine slice prefix.
#
function set_slice_prefix
{
	typeset disk
	typeset -i i=0

	if is_linux; then
		while (( i < $DISK_ARRAY_NUM )); do
			disk="$(echo $DISKS | nawk '{print $(i + 1)}')"
			if ( is_mpath_device $disk ) && [[ -z $(echo $disk | awk 'substr($1,18,1)\
			     ~ /^[[:digit:]]+$/') ]] || ( is_real_device $disk ); then
				export SLICE_PREFIX=""
				return 0
			elif ( is_mpath_device $disk || is_loop_device \
			    $disk ); then
				export SLICE_PREFIX="p"
				return 0
			else
				log_fail "$disk not supported for partitioning."
			fi
			(( i = i + 1))
		done
	fi
}

#
# Set the directory path of the listed devices in $DISK_ARRAY_NUM
# Currently all disks have to be of the same type, so only
# checks first disk to determine device directory
# default = /dev (linux)
# real disk = /dev (linux)
# multipath device = /dev/mapper (linux)
#
function set_device_dir
{
	typeset disk
	typeset -i i=0

	if is_linux; then
		while (( i < $DISK_ARRAY_NUM )); do
			disk="$(echo $DISKS | nawk '{print $(i + 1)}')"
			if is_mpath_device $disk; then
				export DEV_DSKDIR=$DEV_MPATHDIR
				return 0
			else
				export DEV_DSKDIR=$DEV_RDSKDIR
				return 0
			fi
			(( i = i + 1))
		done
	else
		export DEV_DSKDIR=$DEV_RDSKDIR
	fi
}

#
# Get the directory path of given device
#
function get_device_dir #device
{
	typeset device=$1

	if ! $(is_physical_device $device) ; then
		if [[ $device != "/" ]]; then
			device=${device%/*}
		fi
		if [[ -b "$DEV_DSKDIR/$device" ]]; then
			device="$DEV_DSKDIR"
		fi
		echo $device
	else
		echo "$DEV_DSKDIR"
	fi
}

#
# Get persistent name for given disk
#
function get_persistent_disk_name #device
{
	typeset device=$1
	typeset dev_id

	if is_linux; then
		if is_real_device $device; then
			dev_id="$(udevadm info -q all -n $DEV_DSKDIR/$device \
			    | egrep disk/by-id | nawk '{print $2; exit}' \
			    | nawk -F / '{print $3}')"
			echo $dev_id
		elif is_mpath_device $device; then
			dev_id="$(udevadm info -q all -n $DEV_DSKDIR/$device \
			    | egrep disk/by-id/dm-uuid \
			    | nawk '{print $2; exit}' \
			    | nawk -F / '{print $3}')"
			echo $dev_id
		else
			echo $device
		fi
	else
		echo $device
	fi
}

#
# Online or offline a disk on the system
#
# First checks state of disk. Test will fail if disk is not properly onlined
# or offlined. Online is a full rescan of SCSI disks by echoing to every
# host entry.
#
function on_off_disk # disk state{online,offline} host
{
	typeset disk=$1
	typeset state=$2
	typeset host=$3

	[[ -z $disk ]] || [[ -z $state ]] &&  \
	    log_fail "Arguments invalid or missing"

	if is_linux; then
		if [[ $state == "offline" ]] && ( is_mpath_device $disk ); then
			dm_name="$(readlink $DEV_DSKDIR/$disk \
			    | nawk -F / '{print $2}')"
			slave="$(ls /sys/block/${dm_name}/slaves \
			    | nawk '{print $1}')"
			while [[ -n $slave ]]; do
				#check if disk is online
				lsscsi | egrep $slave > /dev/null
				if (($? == 0)); then
					slave_dir="/sys/block/${dm_name}"
					slave_dir+="/slaves/${slave}/device"
					ss="${slave_dir}/state"
					sd="${slave_dir}/delete"
					log_must eval "echo 'offline' > ${ss}"
					log_must eval "echo '1' > ${sd}"
					lsscsi | egrep $slave > /dev/null
						if (($? == 0)); then
							log_fail "Offlining" \
							    "$disk failed"
						fi
				fi
				slave="$(ls /sys/block/$dm_name/slaves \
				    2>/dev/null | nawk '{print $1}')"
			done
		elif [[ $state == "offline" ]] && ( is_real_device $disk ); then
			#check if disk is online
			lsscsi | egrep $disk > /dev/null
			if (($? == 0)); then
				dev_state="/sys/block/$disk/device/state"
				dev_delete="/sys/block/$disk/device/delete"
				log_must eval "echo 'offline' > ${dev_state}"
				log_must eval "echo '1' > ${dev_delete}"
				lsscsi | egrep $disk > /dev/null
					if (($? == 0)); then
						log_fail "Offlining $disk" \
						    "failed"
					fi
			else
				log_note "$disk is already offline"
			fi
		elif [[ $state == "online" ]]; then
			#force a full rescan
			scan_scsi_hosts $host
			block_device_wait
			if is_mpath_device $disk; then
				dm_name="$(readlink $DEV_DSKDIR/$disk \
				    | nawk -F / '{print $2}')"
				slave="$(ls /sys/block/$dm_name/slaves \
				    | nawk '{print $1}')"
				lsscsi | egrep $slave > /dev/null
				if (($? != 0)); then
					log_fail "Onlining $disk failed"
				fi
			elif is_real_device $disk; then
				typeset -i retries=0
				while ! lsscsi | egrep -q $disk; do
					if (( $retries > 2 )); then
						log_fail "Onlining $disk failed"
						break
					fi
					(( ++retries ))
					sleep 1
				done
			else
				log_fail "$disk is not a real dev"
			fi
		else
			log_fail "$disk failed to $state"
		fi
	fi
}

#
# Simulate disk removal
#
function remove_disk #disk
{
	typeset disk=$1
	on_off_disk $disk "offline"
	block_device_wait
}

#
# Simulate disk insertion for the given SCSI host
#
function insert_disk #disk scsi_host
{
	typeset disk=$1
	typeset scsi_host=$2
	on_off_disk $disk "online" $scsi_host
	block_device_wait
}

#
# Load scsi_debug module with specified parameters
# $blksz can be either one of: < 512b | 512e | 4Kn >
#
function load_scsi_debug # dev_size_mb add_host num_tgts max_luns blksz
{
	typeset devsize=$1
	typeset hosts=$2
	typeset tgts=$3
	typeset luns=$4
	typeset blksz=$5

	[[ -z $devsize ]] || [[ -z $hosts ]] || [[ -z $tgts ]] || \
	    [[ -z $luns ]] || [[ -z $blksz ]] && \
	    log_fail "Arguments invalid or missing"

	case "$5" in
		'512b')
			typeset sector=512
			typeset blkexp=0
		;;
		'512e')
			typeset sector=512
			typeset blkexp=3
		;;
		'4Kn')
			typeset sector=4096
			typeset blkexp=0
		;;
		*) log_fail "Unsupported blksz value: $5" ;;
	esac

	if is_linux; then
		modprobe -n scsi_debug
		if (($? != 0)); then
			log_unsupported "Platform does not have scsi_debug"
			    "module"
		fi
		lsmod | egrep scsi_debug > /dev/null
		if (($? == 0)); then
			log_fail "scsi_debug module already installed"
		else
			log_must modprobe scsi_debug dev_size_mb=$devsize \
			    add_host=$hosts num_tgts=$tgts max_luns=$luns \
			    sector_size=$sector physblk_exp=$blkexp
			block_device_wait
			lsscsi | egrep scsi_debug > /dev/null
			if (($? == 1)); then
				log_fail "scsi_debug module install failed"
			fi
		fi
	fi
}

#
# Unload scsi_debug module, if needed.
#
function unload_scsi_debug
{
	if lsmod | grep scsi_debug >/dev/null; then
		log_must modprobe -r scsi_debug
	fi
}

#
# Get scsi_debug device name.
# Returns basename of scsi_debug device (for example "sdb").
#
function get_debug_device
{
	lsscsi | nawk '/scsi_debug/ {print $6; exit}' | cut -d / -f3
}
