#
# 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, 2019 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.
# Copyright 2019 Richard Elling
#

#
# 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.
# Additional arguments can be passed to udevadm trigger, with the expected
# arguments to typically be a block device pathname. This is useful when
# checking waiting on a specific device to settle rather than triggering
# all devices and waiting for them all to settle.
#
# The udevadm settle timeout can be 120 or 180 seconds by default for
# some distros. If a long delay is experienced, it could be due to some
# strangeness in a malfunctioning device that isn't related to the devices
# under test. To help debug this condition, a notice is given if settle takes
# too long.
#
# Note: there is no meaningful return code if udevadm fails. Consumers
# should not expect a return code (do not call as argument to log_must)
#
function block_device_wait
{
	if is_linux; then
		udevadm trigger $*
		typeset start=$SECONDS
		udevadm settle
		typeset elapsed=$((SECONDS - start))
		[[ $elapsed > 60 ]] && \
		    log_note udevadm settle time too long: $elapsed
	elif is_freebsd; then
		if [[ ${#@} -eq 0 ]]; then
			# Do something that has to go through the geom event
			# queue to complete.
			sysctl kern.geom.conftxt >/dev/null
			return
		fi
	fi
	# Poll for the given paths to appear, but give up eventually.
	typeset -i i
	for (( i = 0; i < 5; ++i )); do
		typeset missing=false
		typeset dev
		for dev in "${@}"; do
			if ! [[ -f $dev ]]; then
				missing=true
				break
			fi
		done
		if ! $missing; then
			break
		fi
		sleep ${#@}
	done
}

#
# 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
		is_disk_device "$DEV_DSKDIR/$device" && \
		[[ -f /sys/module/loop/parameters/max_part ]]
		return $?
	elif is_freebsd; then
		is_disk_device "$DEV_DSKDIR/$device" && \
		echo $device | egrep -q \
		    -e '^a?da[0-9]+$' \
		    -e '^md[0-9]+$' \
		    -e '^mfid[0-9]+$' \
		    -e '^nda[0-9]+$' \
		    -e '^nvd[0-9]+$' \
		    -e '^vtbd[0-9]+$'
		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
}

#
# Linux:
# Check if the given device is a multipath device and if there is a symbolic
# link to a device mapper and to a disk
# Currently no support for dm devices alone without multipath
#
# FreeBSD:
# Check if the given device is a gmultipath device.
#
# Others:
# No multipath detection.
#
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
	elif is_freebsd; then
		is_disk_device $DEV_MPATHDIR/$disk
	else
		false
	fi
}

#
# Check if the given path is the appropriate sort of device special node.
#
function is_disk_device #path
{
	typeset path=$1

	if is_freebsd; then
		# FreeBSD doesn't have block devices, only character devices.
		test -c $path
	else
		test -b $path
	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_freebsd && ! is_physical_device $device; then
		if [[ $device != "/" ]]; then
			device=${device%/*}
		fi
		if is_disk_device "$DEV_DSKDIR/$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 $2}')"
			dep="$(ls /sys/block/${dm_name}/slaves \
			    | nawk '{print $1}')"
			while [[ -n $dep ]]; do
				#check if disk is online
				lsscsi | egrep $dep > /dev/null
				if (($? == 0)); then
					dep_dir="/sys/block/${dm_name}"
					dep_dir+="/slaves/${dep}/device"
					ss="${dep_dir}/state"
					sd="${dep_dir}/delete"
					log_must eval "echo 'offline' > ${ss}"
					log_must eval "echo '1' > ${sd}"
					lsscsi | egrep $dep > /dev/null
						if (($? == 0)); then
							log_fail "Offlining" \
							    "$disk failed"
						fi
				fi
				dep="$(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 $2}')"
				dep="$(ls /sys/block/$dm_name/slaves \
				    | nawk '{print $1}')"
				lsscsi | egrep $dep > /dev/null
				if (($? != 0)); then
					log_fail "Onlining $disk failed"
				fi
			elif is_real_device $disk; then
				block_device_wait
				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
{
	log_must_retry "in use" 5 modprobe -r scsi_debug
}

#
# Get scsi_debug device name.
# Returns basename of scsi_debug device (for example "sdb").
#
function get_debug_device
{
	for i in {1..10} ; do
		val=$(lsscsi | nawk '/scsi_debug/ {print $6; exit}' | cut -d / -f3)

		# lsscsi can take time to settle
		if [ "$val" != "-" ] ; then
			break
		fi
		sleep 1
	done
	echo "$val"
}

#
# Get actual devices used by the pool (i.e. linux sdb1 not sdb).
#
function get_pool_devices #testpool #devdir
{
	typeset testpool=$1
	typeset devdir=$2
	typeset out=""

	if is_linux || is_freebsd; then
		out=$(zpool status -P $testpool |grep ${devdir} | awk '{print $1}')
		out=$(echo $out | sed -e "s|${devdir}/||g" | tr '\n' ' ')
	fi
	echo $out
}

#
# Write to standard out giving the level, device name, offset and length
# of all blocks in an input file. The offset and length are in units of
# 512 byte blocks. In the case of mirrored vdevs, only the first
# device is listed, as the levels, blocks and offsets will be the same
# on other devices. Note that this function only works with mirrored
# or non-redundant pools, not raidz.
#
# The output of this function can be used to introduce corruption at
# varying levels of indirection.
#
function list_file_blocks # input_file
{
	typeset input_file=$1

	[[ -f $input_file ]] || log_fail "Couldn't find $input_file"

	typeset ds="$(zfs list -H -o name $input_file)"
	typeset pool="${ds%%/*}"
	typeset objnum="$(get_objnum $input_file)"

	#
	# Establish a mapping between vdev ids as shown in a DVA and the
	# pathnames they correspond to in ${VDEV_MAP[][]}.
	#
	# The vdev bits in a DVA refer to the top level vdev id.
	# ${VDEV_MAP[$id]} is an array of the vdev paths within that vdev.
	#
	eval $(zdb -C $pool | awk '
	    BEGIN { printf "typeset -a VDEV_MAP;" }
	    function subscript(s) {
	        # "[#]" is more convenient than the bare "#"
	        match(s, /\[[0-9]*\]/)
		return substr(s, RSTART, RLENGTH)
	    }
	    id && !/^                / {
	        # left a top level vdev
	        id = 0
	    }
	    id && $1 ~ /^path:$/ {
	        # found a vdev path; save it in the map
	        printf "VDEV_MAP%s%s=%s;", id, child, $2
	    }
	    /^            children/ {
	        # entering a top level vdev
	        id = subscript($0)
		child = "[0]" # default in case there is no nested vdev
		printf "typeset -a VDEV_MAP%s;", id
	    }
	    /^                children/ {
	        # entering a nested vdev (e.g. child of a top level mirror)
	        child = subscript($0)
	    }
	')

	#
	# The awk below parses the output of zdb, printing out the level
	# of each block along with vdev id, offset and length. The last
	# two are converted to decimal in the while loop. 4M is added to
	# the offset to compensate for the first two labels and boot
	# block. Lastly, the offset and length are printed in units of
	# 512B blocks for ease of use with dd.
	#
	typeset level vdev path offset length
	if awk -n '' 2>/dev/null; then
		# gawk needs -n to decode hex
		AWK='awk -n'
	else
		AWK='awk'
	fi
	log_must zpool sync -f
	zdb -dddddd $ds $objnum | $AWK -v pad=$((4<<20)) -v bs=512 '
	    /^$/ { looking = 0 }
	    looking {
	        level = $2
	        field = 3
	        while (split($field, dva, ":") == 3) {
	            # top level vdev id
	            vdev = int(dva[1])
	            # offset + 4M label/boot pad in 512B blocks
	            offset = (int("0x"dva[2]) + pad) / bs
		    # length in 512B blocks
		    len = int("0x"dva[3]) / bs

	            print level, vdev, offset, len

	            ++field
	        }
	    }
	    /^Indirect blocks:/ { looking = 1 }
	' | \
	while read level vdev offset length; do
		for path in ${VDEV_MAP[$vdev][@]}; do
			echo "$level $path $offset $length"
		done
	done 2>/dev/null
}

function corrupt_blocks_at_level # input_file corrupt_level
{
	typeset input_file=$1
	typeset corrupt_level="L${2:-0}"
	typeset level path offset length

	[[ -f $input_file ]] || log_fail "Couldn't find $input_file"

	if is_freebsd; then
		# Temporarily allow corrupting an inuse device.
		debugflags=$(sysctl -n kern.geom.debugflags)
		sysctl kern.geom.debugflags=16
	fi

	list_file_blocks $input_file | \
	while read level path offset length; do
		if [[ $level = $corrupt_level ]]; then
			log_must dd if=/dev/urandom of=$path bs=512 \
			    count=$length seek=$offset conv=notrunc
		fi
	done

	if is_freebsd; then
		sysctl kern.geom.debugflags=$debugflags
	fi

	# This is necessary for pools made of loop devices.
	sync
}
